Added data and parsed the 1000 most used words

README.md

@@ -1,2 +1,24 @@
 # omega
 
+## Sources
+1. Generic news articles
+    - https://edition.cnn.com/2025/03/20/middleeast/ronen-bar-shin-bet-israel-vote-dismiss-intl-latam/index.html
+    - https://edition.cnn.com/2025/03/21/europe/conor-mcgregor-ireland-president-election-intl-hnk/index.html
+
+2. Wikipedia articles
+    - https://simple.wikipedia.org/wiki/Dog
+    - https://en.wikipedia.org/wiki/Car
+
+3. Scientific articles ([Kurzgesagt](https://www.youtube.com/@kurzgesagt/videos))
+    - https://www.youtube.com/watch?v=dCiMUWw1BBc&t=766s
+        - https://news.umich.edu/astronomers-find-surprising-ice-world-in-the-habitable-zone-with-jwst-data/
+    - https://www.youtube.com/watch?v=VD6xJq8NguY
+        - https://www.pnas.org/doi/10.1073/pnas.1711842115
+
+4. License text
+    - https://www.gnu.org/licenses/gpl-3.0.en.html
+    - https://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html
+
+5. Books
+    - https://ia902902.us.archive.org/19/items/diaryofawimpykidbookseriesbyjeffkinney_202004/Diary%20of%20a%20wimpy%20kid%20book02%20rodrick%20rules.pdf
+    - https://drive.google.com/file/d/1b1Etdxb1cNU3PvDBQnYh0bCAAfssMi8b/view

count.sh

@@ -0,0 +1,4 @@
+#!/bin/bash
+
+
+grep -o "[[:alpha:]]\{1,\}" "$1" | tr '[:upper:]' '[:lower:]' | sort | uniq -c | sort -n

data/gpl_2.txt

@@ -0,0 +1,116 @@
+Everyone is permitted to copy and distribute verbatim copies
+of this license document, but changing it is not allowed.
+
+Preamble
+
+The licenses for most software are designed to take away your freedom to share and change it. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change free software--to make sure the software is free for all its users. This General Public License applies to most of the Free Software Foundation's software and to any other program whose authors commit to using it. (Some other Free Software Foundation software is covered by the GNU Lesser General Public License instead.) You can apply it to your programs, too.
+
+When we speak of free software, we are referring to freedom, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for this service if you wish), that you receive source code or can get it if you want it, that you can change the software or use pieces of it in new free programs; and that you know you can do these things.
+
+To protect your rights, we need to make restrictions that forbid anyone to deny you these rights or to ask you to surrender the rights. These restrictions translate to certain responsibilities for you if you distribute copies of the software, or if you modify it.
+
+For example, if you distribute copies of such a program, whether gratis or for a fee, you must give the recipients all the rights that you have. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights.
+
+We protect your rights with two steps: (1) copyright the software, and (2) offer you this license which gives you legal permission to copy, distribute and/or modify the software.
+
+Also, for each author's protection and ours, we want to make certain that everyone understands that there is no warranty for this free software. If the software is modified by someone else and passed on, we want its recipients to know that what they have is not the original, so that any problems introduced by others will not reflect on the original authors' reputations.
+
+Finally, any free program is threatened constantly by software patents. We wish to avoid the danger that redistributors of a free program will individually obtain patent licenses, in effect making the program proprietary. To prevent this, we have made it clear that any patent must be licensed for everyone's free use or not licensed at all.
+
+The precise terms and conditions for copying, distribution and modification follow.
+TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+0. This License applies to any program or other work which contains a notice placed by the copyright holder saying it may be distributed under the terms of this General Public License. The "Program", below, refers to any such program or work, and a "work based on the Program" means either the Program or any derivative work under copyright law: that is to say, a work containing the Program or a portion of it, either verbatim or with modifications and/or translated into another language. (Hereinafter, translation is included without limitation in the term "modification".) Each licensee is addressed as "you".
+
+Activities other than copying, distribution and modification are not covered by this License; they are outside its scope. The act of running the Program is not restricted, and the output from the Program is covered only if its contents constitute a work based on the Program (independent of having been made by running the Program). Whether that is true depends on what the Program does.
+
+1. You may copy and distribute verbatim copies of the Program's source code as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice and disclaimer of warranty; keep intact all the notices that refer to this License and to the absence of any warranty; and give any other recipients of the Program a copy of this License along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and you may at your option offer warranty protection in exchange for a fee.
+
+2. You may modify your copy or copies of the Program or any portion of it, thus forming a work based on the Program, and copy and distribute such modifications or work under the terms of Section 1 above, provided that you also meet all of these conditions:
+
+    a) You must cause the modified files to carry prominent notices stating that you changed the files and the date of any change. 
+    b) You must cause any work that you distribute or publish, that in whole or in part contains or is derived from the Program or any part thereof, to be licensed as a whole at no charge to all third parties under the terms of this License. 
+    c) If the modified program normally reads commands interactively when run, you must cause it, when started running for such interactive use in the most ordinary way, to print or display an announcement including an appropriate copyright notice and a notice that there is no warranty (or else, saying that you provide a warranty) and that users may redistribute the program under these conditions, and telling the user how to view a copy of this License. (Exception: if the Program itself is interactive but does not normally print such an announcement, your work based on the Program is not required to print an announcement.) 
+
+These requirements apply to the modified work as a whole. If identifiable sections of that work are not derived from the Program, and can be reasonably considered independent and separate works in themselves, then this License, and its terms, do not apply to those sections when you distribute them as separate works. But when you distribute the same sections as part of a whole which is a work based on the Program, the distribution of the whole must be on the terms of this License, whose permissions for other licensees extend to the entire whole, and thus to each and every part regardless of who wrote it.
+
+Thus, it is not the intent of this section to claim rights or contest your rights to work written entirely by you; rather, the intent is to exercise the right to control the distribution of derivative or collective works based on the Program.
+
+In addition, mere aggregation of another work not based on the Program with the Program (or with a work based on the Program) on a volume of a storage or distribution medium does not bring the other work under the scope of this License.
+
+3. You may copy and distribute the Program (or a work based on it, under Section 2) in object code or executable form under the terms of Sections 1 and 2 above provided that you also do one of the following:
+
+    a) Accompany it with the complete corresponding machine-readable source code, which must be distributed under the terms of Sections 1 and 2 above on a medium customarily used for software interchange; or, 
+    b) Accompany it with a written offer, valid for at least three years, to give any third party, for a charge no more than your cost of physically performing source distribution, a complete machine-readable copy of the corresponding source code, to be distributed under the terms of Sections 1 and 2 above on a medium customarily used for software interchange; or, 
+    c) Accompany it with the information you received as to the offer to distribute corresponding source code. (This alternative is allowed only for noncommercial distribution and only if you received the program in object code or executable form with such an offer, in accord with Subsection b above.) 
+
+The source code for a work means the preferred form of the work for making modifications to it. For an executable work, complete source code means all the source code for all modules it contains, plus any associated interface definition files, plus the scripts used to control compilation and installation of the executable. However, as a special exception, the source code distributed need not include anything that is normally distributed (in either source or binary form) with the major components (compiler, kernel, and so on) of the operating system on which the executable runs, unless that component itself accompanies the executable.
+
+If distribution of executable or object code is made by offering access to copy from a designated place, then offering equivalent access to copy the source code from the same place counts as distribution of the source code, even though third parties are not compelled to copy the source along with the object code.
+
+4. You may not copy, modify, sublicense, or distribute the Program except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense or distribute the Program is void, and will automatically terminate your rights under this License. However, parties who have received copies, or rights, from you under this License will not have their licenses terminated so long as such parties remain in full compliance.
+
+5. You are not required to accept this License, since you have not signed it. However, nothing else grants you permission to modify or distribute the Program or its derivative works. These actions are prohibited by law if you do not accept this License. Therefore, by modifying or distributing the Program (or any work based on the Program), you indicate your acceptance of this License to do so, and all its terms and conditions for copying, distributing or modifying the Program or works based on it.
+
+6. Each time you redistribute the Program (or any work based on the Program), the recipient automatically receives a license from the original licensor to copy, distribute or modify the Program subject to these terms and conditions. You may not impose any further restrictions on the recipients' exercise of the rights granted herein. You are not responsible for enforcing compliance by third parties to this License.
+
+7. If, as a consequence of a court judgment or allegation of patent infringement or for any other reason (not limited to patent issues), conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot distribute so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not distribute the Program at all. For example, if a patent license would not permit royalty-free redistribution of the Program by all those who receive copies directly or indirectly through you, then the only way you could satisfy both it and this License would be to refrain entirely from distribution of the Program.
+
+If any portion of this section is held invalid or unenforceable under any particular circumstance, the balance of the section is intended to apply and the section as a whole is intended to apply in other circumstances.
+
+It is not the purpose of this section to induce you to infringe any patents or other property right claims or to contest validity of any such claims; this section has the sole purpose of protecting the integrity of the free software distribution system, which is implemented by public license practices. Many people have made generous contributions to the wide range of software distributed through that system in reliance on consistent application of that system; it is up to the author/donor to decide if he or she is willing to distribute software through any other system and a licensee cannot impose that choice.
+
+This section is intended to make thoroughly clear what is believed to be a consequence of the rest of this License.
+
+8. If the distribution and/or use of the Program is restricted in certain countries either by patents or by copyrighted interfaces, the original copyright holder who places the Program under this License may add an explicit geographical distribution limitation excluding those countries, so that distribution is permitted only in or among countries not thus excluded. In such case, this License incorporates the limitation as if written in the body of this License.
+
+9. The Free Software Foundation may publish revised and/or new versions of the General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns.
+
+Each version is given a distinguishing version number. If the Program specifies a version number of this License which applies to it and "any later version", you have the option of following the terms and conditions either of that version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of this License, you may choose any version ever published by the Free Software Foundation.
+
+10. If you wish to incorporate parts of the Program into other free programs whose distribution conditions are different, write to the author to ask for permission. For software which is copyrighted by the Free Software Foundation, write to the Free Software Foundation; we sometimes make exceptions for this. Our decision will be guided by the two goals of preserving the free status of all derivatives of our free software and of promoting the sharing and reuse of software generally.
+
+NO WARRANTY
+
+11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
+END OF TERMS AND CONDITIONS
+How to Apply These Terms to Your New Programs
+
+If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms.
+
+To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively convey the exclusion of warranty; and each file should have at least the "copyright" line and a pointer to where the full notice is found.
+
+one line to give the program's name and an idea of what it does.
+Copyright (C) yyyy  name of author
+
+This program is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License
+as published by the Free Software Foundation; either version 2
+of the License, or (at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, see
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this when it starts in an interactive mode:
+
+Gnomovision version 69, Copyright (C) year name of author
+Gnomovision comes with ABSOLUTELY NO WARRANTY; for details
+type `show w'.  This is free software, and you are welcome
+to redistribute it under certain conditions; type `show c' 
+for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate parts of the General Public License. Of course, the commands you use may be called something other than `show w' and `show c'; they could even be mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your school, if any, to sign a "copyright disclaimer" for the program, if necessary. Here is a sample; alter the names:
+

data/gpl_3.txt

@@ -0,0 +1,215 @@
+ Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
+Preamble
+
+The GNU General Public License is a free, copyleft license for software and other kinds of works.
+
+The licenses for most software and other practical works are designed to take away your freedom to share and change the works. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change all versions of a program--to make sure it remains free software for all its users. We, the Free Software Foundation, use the GNU General Public License for most of our software; it applies also to any other work released this way by its authors. You can apply it to your programs, too.
+
+When we speak of free software, we are referring to freedom, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software (and charge for them if you wish), that you receive source code or can get it if you want it, that you can change the software or use pieces of it in new free programs, and that you know you can do these things.
+
+To protect your rights, we need to prevent others from denying you these rights or asking you to surrender the rights. Therefore, you have certain responsibilities if you distribute copies of the software, or if you modify it: responsibilities to respect the freedom of others.
+
+For example, if you distribute copies of such a program, whether gratis or for a fee, you must pass on to the recipients the same freedoms that you received. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights.
+
+Developers that use the GNU GPL protect your rights with two steps: (1) assert copyright on the software, and (2) offer you this License giving you legal permission to copy, distribute and/or modify it.
+
+For the developers' and authors' protection, the GPL clearly explains that there is no warranty for this free software. For both users' and authors' sake, the GPL requires that modified versions be marked as changed, so that their problems will not be attributed erroneously to authors of previous versions.
+
+Some devices are designed to deny users access to install or run modified versions of the software inside them, although the manufacturer can do so. This is fundamentally incompatible with the aim of protecting users' freedom to change the software. The systematic pattern of such abuse occurs in the area of products for individuals to use, which is precisely where it is most unacceptable. Therefore, we have designed this version of the GPL to prohibit the practice for those products. If such problems arise substantially in other domains, we stand ready to extend this provision to those domains in future versions of the GPL, as needed to protect the freedom of users.
+
+Finally, every program is threatened constantly by software patents. States should not allow patents to restrict development and use of software on general-purpose computers, but in those that do, we wish to avoid the special danger that patents applied to a free program could make it effectively proprietary. To prevent this, the GPL assures that patents cannot be used to render the program non-free.
+
+The precise terms and conditions for copying, distribution and modification follow.
+TERMS AND CONDITIONS
+0. Definitions.
+
+“This License” refers to version 3 of the GNU General Public License.
+
+“Copyright” also means copyright-like laws that apply to other kinds of works, such as semiconductor masks.
+
+“The Program” refers to any copyrightable work licensed under this License. Each licensee is addressed as “you”. “Licensees” and “recipients” may be individuals or organizations.
+
+To “modify” a work means to copy from or adapt all or part of the work in a fashion requiring copyright permission, other than the making of an exact copy. The resulting work is called a “modified version” of the earlier work or a work “based on” the earlier work.
+
+A “covered work” means either the unmodified Program or a work based on the Program.
+
+To “propagate” a work means to do anything with it that, without permission, would make you directly or secondarily liable for infringement under applicable copyright law, except executing it on a computer or modifying a private copy. Propagation includes copying, distribution (with or without modification), making available to the public, and in some countries other activities as well.
+
+To “convey” a work means any kind of propagation that enables other parties to make or receive copies. Mere interaction with a user through a computer network, with no transfer of a copy, is not conveying.
+
+An interactive user interface displays “Appropriate Legal Notices” to the extent that it includes a convenient and prominently visible feature that (1) displays an appropriate copyright notice, and (2) tells the user that there is no warranty for the work (except to the extent that warranties are provided), that licensees may convey the work under this License, and how to view a copy of this License. If the interface presents a list of user commands or options, such as a menu, a prominent item in the list meets this criterion.
+1. Source Code.
+
+The “source code” for a work means the preferred form of the work for making modifications to it. “Object code” means any non-source form of a work.
+
+A “Standard Interface” means an interface that either is an official standard defined by a recognized standards body, or, in the case of interfaces specified for a particular programming language, one that is widely used among developers working in that language.
+
+The “System Libraries” of an executable work include anything, other than the work as a whole, that (a) is included in the normal form of packaging a Major Component, but which is not part of that Major Component, and (b) serves only to enable use of the work with that Major Component, or to implement a Standard Interface for which an implementation is available to the public in source code form. A “Major Component”, in this context, means a major essential component (kernel, window system, and so on) of the specific operating system (if any) on which the executable work runs, or a compiler used to produce the work, or an object code interpreter used to run it.
+
+The “Corresponding Source” for a work in object code form means all the source code needed to generate, install, and (for an executable work) run the object code and to modify the work, including scripts to control those activities. However, it does not include the work's System Libraries, or general-purpose tools or generally available free programs which are used unmodified in performing those activities but which are not part of the work. For example, Corresponding Source includes interface definition files associated with source files for the work, and the source code for shared libraries and dynamically linked subprograms that the work is specifically designed to require, such as by intimate data communication or control flow between those subprograms and other parts of the work.
+
+The Corresponding Source need not include anything that users can regenerate automatically from other parts of the Corresponding Source.
+
+The Corresponding Source for a work in source code form is that same work.
+2. Basic Permissions.
+
+All rights granted under this License are granted for the term of copyright on the Program, and are irrevocable provided the stated conditions are met. This License explicitly affirms your unlimited permission to run the unmodified Program. The output from running a covered work is covered by this License only if the output, given its content, constitutes a covered work. This License acknowledges your rights of fair use or other equivalent, as provided by copyright law.
+
+You may make, run and propagate covered works that you do not convey, without conditions so long as your license otherwise remains in force. You may convey covered works to others for the sole purpose of having them make modifications exclusively for you, or provide you with facilities for running those works, provided that you comply with the terms of this License in conveying all material for which you do not control copyright. Those thus making or running the covered works for you must do so exclusively on your behalf, under your direction and control, on terms that prohibit them from making any copies of your copyrighted material outside their relationship with you.
+
+Conveying under any other circumstances is permitted solely under the conditions stated below. Sublicensing is not allowed; section 10 makes it unnecessary.
+3. Protecting Users' Legal Rights From Anti-Circumvention Law.
+
+No covered work shall be deemed part of an effective technological measure under any applicable law fulfilling obligations under article 11 of the WIPO copyright treaty adopted on 20 December 1996, or similar laws prohibiting or restricting circumvention of such measures.
+
+When you convey a covered work, you waive any legal power to forbid circumvention of technological measures to the extent such circumvention is effected by exercising rights under this License with respect to the covered work, and you disclaim any intention to limit operation or modification of the work as a means of enforcing, against the work's users, your or third parties' legal rights to forbid circumvention of technological measures.
+4. Conveying Verbatim Copies.
+
+You may convey verbatim copies of the Program's source code as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice; keep intact all notices stating that this License and any non-permissive terms added in accord with section 7 apply to the code; keep intact all notices of the absence of any warranty; and give all recipients a copy of this License along with the Program.
+
+You may charge any price or no price for each copy that you convey, and you may offer support or warranty protection for a fee.
+5. Conveying Modified Source Versions.
+
+You may convey a work based on the Program, or the modifications to produce it from the Program, in the form of source code under the terms of section 4, provided that you also meet all of these conditions:
+
+    a) The work must carry prominent notices stating that you modified it, and giving a relevant date.
+    b) The work must carry prominent notices stating that it is released under this License and any conditions added under section 7. This requirement modifies the requirement in section 4 to “keep intact all notices”.
+    c) You must license the entire work, as a whole, under this License to anyone who comes into possession of a copy. This License will therefore apply, along with any applicable section 7 additional terms, to the whole of the work, and all its parts, regardless of how they are packaged. This License gives no permission to license the work in any other way, but it does not invalidate such permission if you have separately received it.
+    d) If the work has interactive user interfaces, each must display Appropriate Legal Notices; however, if the Program has interactive interfaces that do not display Appropriate Legal Notices, your work need not make them do so.
+
+A compilation of a covered work with other separate and independent works, which are not by their nature extensions of the covered work, and which are not combined with it such as to form a larger program, in or on a volume of a storage or distribution medium, is called an “aggregate” if the compilation and its resulting copyright are not used to limit the access or legal rights of the compilation's users beyond what the individual works permit. Inclusion of a covered work in an aggregate does not cause this License to apply to the other parts of the aggregate.
+6. Conveying Non-Source Forms.
+
+You may convey a covered work in object code form under the terms of sections 4 and 5, provided that you also convey the machine-readable Corresponding Source under the terms of this License, in one of these ways:
+
+    a) Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by the Corresponding Source fixed on a durable physical medium customarily used for software interchange.
+    b) Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by a written offer, valid for at least three years and valid for as long as you offer spare parts or customer support for that product model, to give anyone who possesses the object code either (1) a copy of the Corresponding Source for all the software in the product that is covered by this License, on a durable physical medium customarily used for software interchange, for a price no more than your reasonable cost of physically performing this conveying of source, or (2) access to copy the Corresponding Source from a network server at no charge.
+    c) Convey individual copies of the object code with a copy of the written offer to provide the Corresponding Source. This alternative is allowed only occasionally and noncommercially, and only if you received the object code with such an offer, in accord with subsection 6b.
+    d) Convey the object code by offering access from a designated place (gratis or for a charge), and offer equivalent access to the Corresponding Source in the same way through the same place at no further charge. You need not require recipients to copy the Corresponding Source along with the object code. If the place to copy the object code is a network server, the Corresponding Source may be on a different server (operated by you or a third party) that supports equivalent copying facilities, provided you maintain clear directions next to the object code saying where to find the Corresponding Source. Regardless of what server hosts the Corresponding Source, you remain obligated to ensure that it is available for as long as needed to satisfy these requirements.
+    e) Convey the object code using peer-to-peer transmission, provided you inform other peers where the object code and Corresponding Source of the work are being offered to the general public at no charge under subsection 6d.
+
+A separable portion of the object code, whose source code is excluded from the Corresponding Source as a System Library, need not be included in conveying the object code work.
+
+A “User Product” is either (1) a “consumer product”, which means any tangible personal property which is normally used for personal, family, or household purposes, or (2) anything designed or sold for incorporation into a dwelling. In determining whether a product is a consumer product, doubtful cases shall be resolved in favor of coverage. For a particular product received by a particular user, “normally used” refers to a typical or common use of that class of product, regardless of the status of the particular user or of the way in which the particular user actually uses, or expects or is expected to use, the product. A product is a consumer product regardless of whether the product has substantial commercial, industrial or non-consumer uses, unless such uses represent the only significant mode of use of the product.
+
+“Installation Information” for a User Product means any methods, procedures, authorization keys, or other information required to install and execute modified versions of a covered work in that User Product from a modified version of its Corresponding Source. The information must suffice to ensure that the continued functioning of the modified object code is in no case prevented or interfered with solely because modification has been made.
+
+If you convey an object code work under this section in, or with, or specifically for use in, a User Product, and the conveying occurs as part of a transaction in which the right of possession and use of the User Product is transferred to the recipient in perpetuity or for a fixed term (regardless of how the transaction is characterized), the Corresponding Source conveyed under this section must be accompanied by the Installation Information. But this requirement does not apply if neither you nor any third party retains the ability to install modified object code on the User Product (for example, the work has been installed in ROM).
+
+The requirement to provide Installation Information does not include a requirement to continue to provide support service, warranty, or updates for a work that has been modified or installed by the recipient, or for the User Product in which it has been modified or installed. Access to a network may be denied when the modification itself materially and adversely affects the operation of the network or violates the rules and protocols for communication across the network.
+
+Corresponding Source conveyed, and Installation Information provided, in accord with this section must be in a format that is publicly documented (and with an implementation available to the public in source code form), and must require no special password or key for unpacking, reading or copying.
+7. Additional Terms.
+
+“Additional permissions” are terms that supplement the terms of this License by making exceptions from one or more of its conditions. Additional permissions that are applicable to the entire Program shall be treated as though they were included in this License, to the extent that they are valid under applicable law. If additional permissions apply only to part of the Program, that part may be used separately under those permissions, but the entire Program remains governed by this License without regard to the additional permissions.
+
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data/kurzgesagt_aliens.txt

@@ -0,0 +1,70 @@
+Significance
+
+Our understanding of life on exoplanets and exomoons must be based on what we know about life on Earth. Liquid water is the common ecological requirement for Earth life. Temperature on an exoplanet is the first parameter to consider both because of its influence on liquid water and because it can be directly estimated from orbital and climate models of exoplanetary systems. Life needs some water, but deserts show that even a little can be enough. Only a small amount of light from the central star is required to provide for photosynthesis. Some nitrogen must be present for life and the presence of oxygen would be a good indicator of photosynthesis and possibly complex life.
+Abstract
+
+The requirements for life on Earth, its elemental composition, and its environmental limits provide a way to assess the habitability of exoplanets. Temperature is key both because of its influence on liquid water and because it can be directly estimated from orbital and climate models of exoplanetary systems. Life can grow and reproduce at temperatures as low as −15 °C, and as high as 122 °C. Studies of life in extreme deserts show that on a dry world, even a small amount of rain, fog, snow, and even atmospheric humidity can be adequate for photosynthetic production producing a small but detectable microbial community. Life is able to use light at levels less than 10−5 of the solar flux at Earth. UV or ionizing radiation can be tolerated by many microorganisms at very high levels and is unlikely to be life limiting on an exoplanet. Biologically available nitrogen may limit habitability. Levels of O2 over a few percent on an exoplanet would be consistent with the presence of multicellular organisms and high levels of O2 on Earth-like worlds indicate oxygenic photosynthesis. Other factors such as pH and salinity are likely to vary and not limit life over an entire planet or moon.
+
+The list of exoplanets is increasing rapidly with a diversity of masses, orbital distances, and star types. The long list motivates us to consider which of these worlds could support life and what type of life could live there. The only approach to answering these questions is based on observations of life on Earth. Compared with astronomical targets, life on Earth is easily studied and our knowledge of it is extensive––but it is not complete. The most important area in which we lack knowledge about life on Earth is its origin. We have no consensus theory for the origin of life nor do we know the timing or location (1). What we do know about life on Earth is what it is made of, and we know its ecological requirements and limits. Thus, it is not surprising that most of the discussions related to life on exoplanets focus on the requirements for life rather than its origin. In this paper we follow this same approach but later return briefly to the question of the origin of life.
+Limits to Life
+
+There are two somewhat different approaches to the question of the limits of life. The first approach is to determine the requirements for life. The second approach is to determine the extreme environments in which adapted organisms—often referred to as extremophiles—can survive. Both perspectives are relevant to the question of life on exoplanets.
+
+It is useful to categorize the requirements for life on Earth as four items: energy, carbon, liquid water, and various other elements. These are listed in Table 1 along with the occurrence of these factors in the Solar System (2). In our Solar System it is the occurrence of liquid water that appears to limit the occurrence of habitable environments and this appears to be the case for exoplanetary systems as well.
+
+From basic thermodynamic considerations it is clear that life requires a source of energy. To power metabolism and growth, life on Earth uses only one energy source: that associated with the transfer of electrons by chemical reactions of reduction and oxidation. For example, methane-producing microbes use the reaction of CO2 with H2 to produce CH4. Photosynthetic organisms use a light-absorbing protein, such as chlorophyll, bacteriochlorophylls, and bacteriorhodopsin, to convert photon energy to the energy of an electron which then completes a redox reaction. The electrons from the redox reaction are used to create an electrochemical gradient across cell membranes (3). This occurs in the mitochondria in of most eukaryotes and in the cell membrane of prokaryotic cells. It has recently been shown that electrons provided directly as electrical current can also drive microbial metabolism (4). Although life can detect and generate other energy sources including magnetic, kinetic, gravitational, thermal gradient, and electrostatic, none of these is used for metabolic energy.
+
+Carbon has the dominant role as the backbone molecule of biochemistry for Earth life and is widespread in the Solar System. However, the abundance of carbon may not be a useful indication of the habitability of an exoplanet. This is illustrated in Fig. 1, which shows that the Earth is significantly depleted in carbon compared with the outer Solar System. The vast majority of the carbon on Earth is stored in sedimentary rocks within the crust. However, because light carbon-containing molecules are volatile––CO2, CO, and CH4––adequate carbon is present at the surface of the Earth, as well as Mars and Venus.
+
+leading candidates for the status of required elements. Table 2, adapted from Davies and Koch (5), lists the distribution of elements in the cosmos and on the Earth and compares these with the common elements in life––represented by humans and the bacterium Escherichia coli. If liquid water and biologically available nitrogen are present, then phosphorous, potassium, sodium, sulfur, and calcium might come next on a requirements list, as these are the next most abundant elements in bacteria. However, there is no definitive list and any list would depend on the organism considered; for example habitability for methanogens requires high nickel levels (6). In a strict sense habitability can only be confirmed by showing inhabitation; no list is conclusive. Of these secondary elements N is probably the one most likely to be in question on an exoplanet, as is discussed below. Sulfur and phosphorous and virtually all of the rest of the elements listed by Davies and Koch (5) as used in life have major refractory phases at the temperatures of liquid water and should be available if water and rock interact.
+
+The second approach to the requirements for life is that based on the abilities of extremophiles in a range of environmental factors. Table 3 lists the limits of life under extreme conditions. Our understanding of the requirements for life listed in Table 1 has not changed for many years. In contrast, the limits of life listed in Table 3 have changed in several significant ways over the past few decades. If one compares a list of the limits of life from a few decades ago (7) with Table 3, the most notable change is in the high-temperature limit. This has been raised from 80 °C to 122 °C (8). There has been considerable discussion on the limits of life and their application to the search for life on other worlds (9–11) and it has been realized that the limits vary when organisms face multiple extreme conditions at the same time 
+
+Whereas the limits of life have changed in some ways over the past few decades, there has been a more radical change in our appreciation of where microbial ecosystems can be found. Notable examples of the discovery of unexpected microbial ecosystems include endolithic microorganisms in the Antarctic cold desert (13), hot deep-sea vents (14), cool deep-sea vents (15), deep in basalt (16), deep below the subsurface (17), and in an ice-covered Antarctic lake that has been sealed for thousands of years (18). Several aspects of these recently discovered ecosystems are worth comment: first, the organisms found are not alien and map in expected areas of the tree of life; second, with the exception of the high-temperature vents, the organisms do not greatly extend the limits of life derived from more mundane and accessible ecosystems; third, the organisms themselves do not find these unusual environments extreme and typically are well adapted to the conditions under which they live; and fourth, the organisms in these environments do not in general control the physical environment (temperature and pressure) with their own metabolic activity but rather live in locations where the local physical conditions are suitable even when these environments are nestled within larger inhospitable areas. The lesson to be learned from these discoveries is that microbial life is extremely adept at locating places to live, and we have not been adept at anticipating how small environments can be habitable in otherwise barren locations: microbial life is more clever than we are. This is a factor that should inform our consideration of habitability of exoplanets.
+Strategy for Exoplanets
+
+Given the general requirements for life (Table 1), the elemental composition of life (Table 2), and the environmental limits for life (Table 3), we can consider how to assess the habitability of the environment on an exoplanet. It may seem logical to focus on primary production because without that there cannot be an ecosystem. However, it is possible that photochemical processes in an exoplanet atmosphere play the role of primary production as has been suggested for Titan (19). Many of the limits to life in Table 3 such as pH and salinity are unlikely to be extreme over an entire world. As on Earth they would shape the distribution of life on a world but not its possible occurrence and are therefore not considered further. The key parameters that could be extreme over an entire world and the order in which they may limit any life on an exoplanet are listed in 
+
+he most important parameter for Earth-like life is the presence of liquid water, which directly depends on pressure and temperature. Temperature is key both because of its influence on liquid water and because it can be directly estimated from orbital and climate models of exoplanetary systems. We can consider the cold and hot limits.
+Temperature, Cold Limit.
+
+Many organisms can grow and reproduce at temperatures well below the freezing point of pure water because their intracellular material contains salts and other solutes that lower the freezing point of the solution. Recently, Mykytczuk et al. (20) reported an isolate from Arctic permafrost that grows and divides at −15 °C, the lowest temperature demonstrated to date, and is metabolically active at −25 °C in frozen soils. Thin films of water at the interface between ice and soil grains, augmented by any solutes, provide adequate water for life at these low temperatures (20, 21). The snow algae Chlamydomonas nivalis thrives in liquid water associated with snow, coloring it red, but the algae are the beneficiaries of external processes that melt the snow (22, 23). Microbial activity can generate sufficient heat in permafrost soils (and landfills and composts) such that it is a major contributor to melting (24, 25), but there is no known occurrence of an organism using metabolic energy coupled directly, e.g., through enzymes, to overcome the latent heat of fusion of ice thereby liquefying it.
+Temperature, Hot Limit.
+
+Many of the exoplanets discovered to date have high surface temperatures and hence the high-temperature limit of life is of particular interest. Takai et al. (8) showed growth, survival, and methane production by a methanogen at 122 °C where the high pressure (20 MPa, ∼200 atmospheres) stabilized the liquid water. At higher pressure water can be liquid at even higher temperatures. However, as water is heated and maintained as a liquid under pressure, the dielectric constant and the polarity of the liquid decreases sharply, thus significantly changing its characteristics as a solvent and its interaction with dissolved biomolecules, in particular lipids, but also proteins and nucleic acids. At 200 °C the dielectric constant is about half of the room temperature value (26). It is likely that the destabilization of lipid bilayers as they become soluble in the lower dielectric constant water is what sets the high-temperature limit on life. It is therefore perhaps not surprising that the organisms that can survive the highest temperatures are archaea (8, 27), as their membrane lipids are held together with ether bonds, which are chemically more resistant than ester bonds, which are used in the membranes of nonarchaea. Denaturing of proteins with temperature appears also to play a role (28). Hot water in contact with rocks can be efficient in generating or recycling redox couples––this has been suggested for the interior of Enceladus (29). Such ecosystems provide a compelling example of possible life below the ocean of an exoplanet or exomoon and can even be productive enough to support multicellular life––in the presence of an O2-rich environment. Fig. 2 shows a crab at the Lost City hydrothermal vent.
+
+Water, Dry Limit.
+
+On worlds where the temperature is within the range discussed above, life may be limited by the availability of water; Mars is an example of this. Thus, the dry limit of life is of interest. In dry environments phototrophs seek shelter and water retained in, and below, rocks. Fig. 3 shows photosynthetic cyanobacteria and lichens from several dry deserts. Fig. 3A shows endolithic cyanobacteria which live just below the surface of halite rocks in the dry core of the Atacama Desert (30). The water to support their growth comes from absorption of atmospheric moisture by the deliquescence of the salt (31). Fig. 3B shows the green biofilm of cyanobacteria that live beneath translucent rocks in many deserts surviving on as little as a few days of rain or fog each year (32–34). The example shown is from an unusual carbonate rock from the Mojave Desert that is clear inside but covered with a red coating (35, 36). Fig. 3C shows lichen forming a green and black layer inside sandstone from the Dry Valleys of Antarctica, which obtain water from melting of occasional snow (37, 38). These examples show that a small amount of rain, fog, or snow and even atmospheric humidity can be adequate for photosynthetic production producing a small but detectable microbial community.
+
+Photosynthesis in dry environments. In the driest environments on Earth, photosynthesis occurs inside and under rocks. (A) Green layer of cyanobacteria living just below the surface of halite rocks in the dry core of the Atacama Desert (30). (B) Inverted samples of red-coated, carbonate translucent rocks from the Mojave desert showing green biofilm of cyanobacteria that live beneath the rock (32, 35, 36). (C) Lichen forming a green and black layer inside sandstone from the Dry Valleys of Antarctica (37). Scale bar in all images, 1 cm. Images A, B, and C are courtesy of J. Wierzchos, C. McKay, and E.I. Friedmann, respectively.
+
+Energy.
+
+Energy for life can come from chemical redox couples generated by geothermal processes or light from the central star. Geothermal flux can arise from (i) the planet cooling off from its gravitational heat of formation, (ii) decay of long-lived radioactive elements, or (iii) tidal heating for a close-orbiting world or moon. Note that on Earth only a tiny fraction of the geothermal heat is converted into chemical energy, whereas about half the solar flux occurs at wavelengths that are usable for photosynthesis. This is expected as the free energy available in heat flow is much less than that available in low-entropy photons. The example of Earth indicates that a biosphere can have effects on a global scale, and hence be detectable over interstellar distances, only when it is powered by light. Life based on geothermally derived chemical energy would, by dint of energy restrictions, always remain small and globally insignificant. Life is able to use light at very low levels. Littler et al. (39) reported on growth of red macroalgae on deep seamounts at light levels of 0.01 μmol m−2⋅s−1. Raven et al. (40) have reviewed the minimum light levels for photosynthesis and also concluded that 0.01 μmol m−2⋅s−1 is needed (40) or ∼5 × 10−6 of the direct solar flux at Earth (2,000 μmol m−2⋅s−1). Even at the orbit of Pluto, light levels exceed this value by a factor of ∼100. It has been suggested that exoplanets around M stars––a common star type which radiates more in the infrared compared with the Sun––could support photosynthesis using a three- or four-photon mechanism photon instead of the two-photon system used in plants on Earth (41).
+UV and Radiation.
+
+Complex life forms (such as humans) are sensitive to radiation but the dose that can be tolerated by many microorganisms is astonishingly high given natural levels of radiation in the environment. Table 3 lists the tolerances and acute dose survival for Deinococcus radiodurans, a well-studied soil heterotroph with high radiation tolerance (42). It has been suggested that the high radiation tolerance of D. radiodurans is due to adaptation to dehydration stress (43). Desert cyanobacteria of the genus Chroococcidiopsis (shown in their characteristic hypolithic growth form in Fig. 3B) are extremely resistant to desiccation, ionizing radiation, and UV (44, 45). An exoplanet would not require a magnetic field to be habitable. Any plausible field would not deflect galactic cosmic rays because these particles are much too energetic. These particles are primarily stopped by the mass of the atmosphere or surface materials. The column mass Earth's atmosphere is equivalent to 1 kg/cm2. The Earth's magnetic field does deflect solar protons channeling these particles to the polar regions creating the aurora. However, even without the magnetic field these particles would not penetrate the Earth's atmosphere and would not reach the surface. Earth occasionally loses its strong dipole field during field reversals. These events are not correlated with extinctions in the fossil record.
+Nitrogen.
+
+Life requires a source of nitrogen. After carbon, nitrogen is arguably the most important element needed for life (46). Experiments have shown that aerobic microorganisms require a minimum of 1–5 × 10−3 atmospheres N2 for fixation (47). A variety of energetic processes such as aurorae, lightning, and volcanoes can convert N2 to nitrate even in CO2 atmospheres (48). In the reducing conditions of the outer Solar System N is present as ammonia which is also biologically usable. The biological availability of nitrogen in an important factor in the assignment of habitability for Mars (49, 50).
+O2.
+
+Multicellular life on Earth generally relies on oxygen metabolism, and the rise of multicellular life over Earth history tracked the rise of oxygen (51). There are interesting exceptions to the connection between oxygen and multicellular life (52, 53) and the link to O2 may be in need of further scrutiny (54). Nonetheless, levels of O2 over a few percent on an exoplanet would be consistent with, and possibly indicative of, the presence of multicellular organisms. Owen (55) suggested that O2 and O3 would be suitable targets for spectroscopy in the search for evidence of life on exoplanets and exomoons. It is generally agreed that high levels of O2 on Earth-like worlds indicate photosynthesis.
+Origin of Life
+
+Discussions of life on an exoplanet should logically begin with a consideration of the possible origin of life on that world. However, our understanding of the origin of life is speculative and so we can only assume that planets that have a diversity of habitable environments are also generative of life (1).
+
+As shown in Fig. 4, it is useful to divide theories for the origin of life on Earth into two main categories, depending on whether life originated independently on a world or was carried to that world from somewhere else (1). The latter category is usually called panspermia, and versions that involve both natural and directed panspermia have been considered (1).
+
+There are possible panspermia schemes that are relevant to exoplanets. Napier (56) has proposed that life could be carried on dust between stars (see also ref. 57), and others have suggested rocks could travel between star systems (58, 59). If such dust grains or rocks were incorporated into the preplanetary nebula, then every planet and moon that formed would be infected with life.
+
+Theories for the origin of life that propose that life on Earth began on Earth are labeled as “Terrestrial” in Fig. 4 and could apply to suitable exoplanets as well. A key question for life on exoplanets is how long the habitable conditions––liquid water––must persist for life to begin. The fossil record on Earth provides only broad constraints on how long it took for life to start on this planet. Simulations of the formation of Earth suggest that habitable conditions were present no sooner than 3.9 billion y ago. The earliest indication of possible life is present in the carbon isotope record at 3.8 billion y ago (60, 61), and convincing evidence of life is present at 3.4 billion y ago (62). Thus, the origin of life occurred within 100–500 million y after the formation of Earth. This is only an upper limit, however, and the process may have been much faster. In a review of this question, Lazcano and Miller (63) suggested that “in spite of the many uncertainties involved in the estimates of time for life to arise and evolve to cyanobacteria, we see no compelling reason to assume that this process, from the beginning of the primitive soup to cyanobacteria, took more than 10 million years.” However, Orgel (64) criticized this conclusion and stated that we do not understand the steps that lead to life; consequently, we cannot estimate the time required: “Attempts to circumvent this essential difficulty are based on misunderstandings of the nature of the problem.” Thus, until new data are obtained the problem of origin of life remains unsolvable.
+Titan Life
+
+In the previous sections, the considerations of life on exoplanets have centered on Earth-like life requiring liquid water. This is certainly a reasonable starting point in the search for life. However, it may be that liquids other than water are also suitable media for carbon-based life forms. Benner et al. (65) first suggested that the liquid hydrocarbons on Titan could be the basis for life, playing the role that water does for life on Earth. Those researchers concluded that in many senses, hydrocarbon solvents are better than water for managing complex organic chemical reactivity. There is also suitable redox energy available for life. Organic molecules on the surface of Titan (such as acetylene, ethane, and solid organics) would release energy if they reacted with hydrogen present in the atmosphere forming methane (19, 66). Acetylene yields the most energy. However, all these reactions are kinetically inhibited and thus could be used by biology if suitable catalysts were evolved. Based on this, McKay and Smith (19) predicted that a sign of life on a Titan-like world would be a depletion of hydrogen, acetylene, and ethane. Lunine (67) suggested that Titan-like worlds and moons might be more common in the galaxy than Earth-like worlds. Gilliam and McKay (68) showed how Titan-like worlds orbiting M-type stars could maintain liquid methane and ethane surface reservoirs.
+
+Titan is an example moon that is of interest with respect to astrobiology. In our Solar System Europa and Enceladus are similarly of interest. Indeed, Enceladus seems to have all of the requirements for habitability (69). It has long been recognized that moons of giant planets may be warmed by tidal heating from the primary planet and receive sufficient light from a central star to power photosynthesis (70). This provides a model for possible habitable moons orbiting giant exoplanets (71).
+Conclusion
+
+As the number of known exoplanets and exomoons expands we will certainly find worlds that resemble the Earth to varying extent. Based on our understanding of life on Earth we can present a checklist for speculating on the possibilities of life on these distant worlds. (i) Is the temperature between −15 °C and 122 °C, and a total pressure high enough to keep water liquid water stable (P > ∼0.01 atmospheres)? (ii) If the world is arid, are there at last a few days per year of rain, fog, snow, or RH > 80%? (iii) Are there adequate light or geothermal energy sources––light determined by distance from the star, geothermal energy estimated by bulk density? (iv) Are the UV and ionizing radiation below the (very high) limits of microbial tolerance? (v) Is there a biologically available source of nitrogen? (vi) If O2 is present at over 0.01 atmospheres there could be complex life, and the presence of O2 is convincing indicator of photosynthetic life on Earth-like worlds.

data/kurzgesagt_deep_life.txt

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+Significance
+
+The composition of the biosphere is a fundamental question in biology, yet a global quantitative account of the biomass of each taxon is still lacking. We assemble a census of the biomass of all kingdoms of life. This analysis provides a holistic view of the composition of the biosphere and allows us to observe broad patterns over taxonomic categories, geographic locations, and trophic modes.
+Abstract
+
+A census of the biomass on Earth is key for understanding the structure and dynamics of the biosphere. However, a global, quantitative view of how the biomass of different taxa compare with one another is still lacking. Here, we assemble the overall biomass composition of the biosphere, establishing a census of the ≈550 gigatons of carbon (Gt C) of biomass distributed among all of the kingdoms of life. We find that the kingdoms of life concentrate at different locations on the planet; plants (≈450 Gt C, the dominant kingdom) are primarily terrestrial, whereas animals (≈2 Gt C) are mainly marine, and bacteria (≈70 Gt C) and archaea (≈7 Gt C) are predominantly located in deep subsurface environments. We show that terrestrial biomass is about two orders of magnitude higher than marine biomass and estimate a total of ≈6 Gt C of marine biota, doubling the previous estimated quantity. Our analysis reveals that the global marine biomass pyramid contains more consumers than producers, thus increasing the scope of previous observations on inverse food pyramids. Finally, we highlight that the mass of humans is an order of magnitude higher than that of all wild mammals combined and report the historical impact of humanity on the global biomass of prominent taxa, including mammals, fish, and plants.
+Sign up for PNAS alerts.
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+Get alerts for new articles, or get an alert when an article is cited.
+
+One of the most fundamental efforts in biology is to describe the composition of the living world. Centuries of research have yielded an increasingly detailed picture of the species that inhabit our planet and their respective roles in global ecosystems. In describing a complex system like the biosphere, it is critical to quantify the abundance of individual components of the system (i.e., species, broader taxonomic groups). A quantitative description of the distribution of biomass is essential for taking stock of biosequestered carbon (1) and modeling global biogeochemical cycles (2), as well as for understanding the historical effects and future impacts of human activities.
+
+Earlier efforts to estimate global biomass have mostly focused on plants (3–5). In parallel, a dominant role for prokaryotic biomass has been advocated in a landmark paper by Whitman et al. (6) entitled “Prokaryotes: The unseen majority.” New sampling and detection techniques (7, 8) make it possible to revisit this claim. Likewise, for other taxa, such as fish, recent global sampling campaigns (9) have resulted in updated estimates, often differing by an order of magnitude or more from previous estimates. For groups such as arthropods, global estimates are still lacking (10, 11).
+
+All of the above efforts are each focused on a single taxon. We are aware of only two attempts at a comprehensive accounting of all biomass components on Earth: Whittaker and Likens (12) made a remarkable effort in the early 1970s, noting even then that their study was “intended for early obsolescence.” It did not include, for example, bacterial or fungal biomass. The other attempt, by Smil (13), was included as a subsection of a book intended for a broad readership. His work details characteristic values for the biomass of various taxa in many environments. Finally, Wikipedia serves as a highly effective platform for making accessible a range of estimates on various taxa (https://en.wikipedia.org/wiki/Biomass_(ecology)#Global_biomass) but currently falls short of a comprehensive or integrated view.
+
+In the past decade, several major technological and scientific advances have facilitated an improved quantitative account of the biomass on Earth. Next-generation sequencing has enabled a more detailed and cultivation-independent view of the composition of natural communities based on the relative abundance of genomes (14). Better remote sensing tools enable us to probe the environment on a global scale with unprecedented resolution and specificity. The Tara Oceans expedition (15) is among recent efforts at global sampling that are expanding our view and coverage. Continental counterpart efforts, such as the National Ecological Observatory Network in North America, add more finely resolved, continent-specific details, affording us more robust descriptions of natural habitats.
+
+Here, we either assemble or generate estimates of the biomass for each of the major taxonomic groups that contribute to the global biomass distribution. Our analysis (described in detail in SI Appendix) is based on hundreds of studies, including recent studies that have overturned earlier estimates for many taxa (e.g., fish, subsurface prokaryotes, marine eukaryotes, soil fauna).
+Results
+The Biomass Distribution of the Biosphere by Kingdom.
+
+In Fig. 1 and Table 1, we report our best estimates for the biomass of each taxon analyzed. We use biomass as a measure of abundance, which allows us to compare taxa whose members are of very different sizes. Biomass is also a useful metric for quantifying stocks of elements sequestered in living organisms. We report biomass using the mass of carbon, as this measure is independent of water content and has been used extensively in the literature (6, 16, 17). Alternative measures for biomass, such as dry weight, are discussed in Materials and Methods. For ease of discussion, we report biomass in gigatons of carbon, with 1 Gt C = 1015 g of carbon. We supply additional estimates for the number of individuals of different taxa in 
+
+Whereas groups like insects dominate in terms of species richness [with about 1 million described species (23)], their relative biomass fraction is miniscule. Some species contribute much more than entire families or even classes. For example, the Antarctic krill species Euphausia superba contributes ≈0.05 Gt C to global biomass (24), similar to other prominent species such as humans or cows. This value is comparable to the contribution from termites (25), which contain many species, and far surpasses the biomass of entire vertebrate classes such as birds. In this way, the picture that arises from taking a biomass perspective of the biosphere complements the focus on species richness that is commonly held (SI Appendix, Fig. S3).
+The Uncertainty Associated with Global Biomass Estimates.
+
+The specific methods used for each taxon are highly diverse and are given in detail in the SI Appendix, along with data sources. Global biomass estimates vary in the amount of information they are based on and, consequently, in their uncertainty. An estimate of relatively high certainty is that of plants, which is based on several independent sources. One of these is the Forest Resource Assessment, a survey on the state of world forests conducted by the international Food and Agriculture Organization (FAO). The assessment is based on a collection of country reports that detail the area and biomass density of forests in each country (26) using a standardized format and methodology. The FAO also keeps a record of nonforest ecosystems, such as savannas and shrublands, in each country. Alternatively, remote sensing data give high coverage of measurements that indicate plant biomass (27–29). Remote sensing is used to measure, for example, the height of trees or the number of tree stems per unit area. Biomass is inferred by field measurements establishing a connection between tree plant biomass and satellite-based remote sensing measurements. Combining data from independent sources such as these enables a robust assessment of the total plant biomass (17).
+
+A more characteristic case with larger uncertainties is exemplified by marine prokaryotes, where cell concentrations are measured in various locations and binned based on depth. For each depth range, the average cell concentration is calculated and the total number of marine prokaryotes is estimated through multiplication by the water volume in each depth range. The total number of cells is converted to biomass by using the characteristic carbon content per marine prokaryote. In cases where there are fewer measurements (e.g., terrestrial arthropods, terrestrial protists), the possibility of systematic biases in the estimate is greater and the uncertainty larger. To test the robustness of our estimates, we used independent approaches and analyzed the agreement between such independent estimates. Details on the specific methodologies used for each taxon are provided in the SI Appendix. Because most datasets used to estimate global biomass rely on fragmentary sampling, we project large uncertainties that will be reduced as additional data become available.
+The Impact of Humanity on the Biosphere.
+
+Over the relatively short span of human history, major innovations, such as the domestication of livestock, adoption of an agricultural lifestyle, and the Industrial Revolution, have increased the human population dramatically and have had radical ecological effects. Today, the biomass of humans (≈0.06 Gt C; SI Appendix, Table S9) and the biomass of livestock (≈0.1 Gt C, dominated by cattle and pigs; SI Appendix, Table S10) far surpass that of wild mammals, which has a mass of ≈0.007 Gt C (SI Appendix, Table S11). This is also true for wild and domesticated birds, for which the biomass of domesticated poultry (≈0.005 Gt C, dominated by chickens) is about threefold higher than that of wild birds (≈0.002 Gt C; SI Appendix, Table S12). In fact, humans and livestock outweigh all vertebrates combined, with the exception of fish. Even though humans and livestock dominate mammalian biomass, they are a small fraction of the ≈2 Gt C of animal biomass, which primarily comprises arthropods (≈1 Gt C; SI Appendix, Tables S13 and S14), followed by fish (≈0.7 Gt C; SI Appendix, Table S15). Comparison of current global biomass with prehuman values (which are very difficult to estimate accurately) demonstrates the impact of humans on the biosphere. Human activity contributed to the Quaternary Megafauna Extinction between ≈50,000 and ≈3,000 y ago, which claimed around half of the large (>40 kg) land mammal species (30). The biomass of wild land mammals before this period of extinction was estimated by Barnosky (30) at ≈0.02 Gt C. The present-day biomass of wild land mammals is approximately sevenfold lower, at ≈0.003 Gt C (SI Appendix, Pre-human Biomass and Chordates and Table S11). Intense whaling and exploitation of other marine mammals have resulted in an approximately fivefold decrease in marine mammal global biomass [from ≈0.02 Gt C to ≈0.004 Gt C (31)]. While the total biomass of wild mammals (both marine and terrestrial) decreased by a factor of ≈6, the total mass of mammals increased approximately fourfold from ≈0.04 Gt C to ≈0.17 Gt C due to the vast increase of the biomass of humanity and its associated livestock. Human activity has also impacted global vertebrate stocks, with a decrease of ≈0.1 Gt C in total fish biomass, an amount similar to the remaining total biomass in fisheries and to the gain in the total mammalian biomass due to livestock husbandry (SI Appendix, Pre-human Biomass). The impact of human civilization on global biomass has not been limited to mammals but has also profoundly reshaped the total quantity of carbon sequestered by plants. A worldwide census of the total number of trees (32), as well as a comparison of actual and potential plant biomass (17), has suggested that the total plant biomass (and, by proxy, the total biomass on Earth) has declined approximately twofold relative to its value before the start of human civilization. The total biomass of crops cultivated by humans is estimated at ≈10 Gt C, which accounts for only ≈2% of the extant total plant biomass (17).
+The Distribution of Biomass Across Environments and Trophic Modes.
+
+Examining global biomass in different environments exposes stark differences between terrestrial and marine environments. The ocean covers 71% of the Earth’s surface and occupies a much larger volume than the terrestrial environment, yet land biomass, at ≈470 Gt C, is about two orders of magnitude higher than the ≈6 Gt C in marine biomass, as shown in Fig. 2A. Even though there is a large difference in the biomass content of the terrestrial and marine environments, the primary productivity of the two environments is roughly equal (33). For plants, we find that most biomass is concentrated in terrestrial environments (plants have only a small fraction of marine biomass, <1 Gt C, in the form of green algae and seagrass; Fig. 2B). For animals, most biomass is concentrated in the marine environment, and for bacteria and archaea, most biomass is concentrated in deep subsurface environments. We note that several of the results in Fig. 2B should be interpreted with caution due to the large uncertainty associated with some of the estimates, mostly those of total terrestrial protists, marine fungi, and contributions from deep subsurface environments.
+
+When analyzing trophic levels, the biomass of primary producers on land is much larger than that of primary and secondary consumers. In stark contrast, in the oceans, ≈1 Gt C of primary producers supports ≈5 Gt C of consumer biomass, resulting in an inverted standing biomass distribution as shown in Fig. 2C. Such inverted biomass distributions can occur when primary producers have a rapid turnover of biomass [on the order of days (34)], while consumer biomass turns over much more slowly [a few years in the case of mesopelagic fish (35)]. Thus, the standing stock of consumers is larger, even though the productivity of producers is necessarily higher. Previous reports have observed inverted biomass pyramids in local marine environments (36, 37). An additional study noted an inverted consumer/producer ratio for the global plankton biomass (16). Our analysis suggests that these observations hold true when looking at the global biomass of all producers and consumers in the marine environment.
+Discussion
+
+Our census of the distribution of biomass on Earth provides an integrated global picture of the relative and absolute abundances of all kingdoms of life. We find that the biomass of plants dominates the biomass of the biosphere and is mostly located on land. The marine environment is primarily occupied by microbes, mainly bacteria and protists, which account for ≈70% of the total marine biomass. The remaining ≈30% is mainly composed of arthropods and fish. The deep subsurface holds ≈15% of the total biomass in the biosphere. It is chiefly composed of bacteria and archaea, which are mostly surface-attached and turn over their biomass every several months to thousands of years (18–22).
+
+In addition to summarizing current knowledge of the global biomass distribution, our work highlights gaps in the current understanding of the biosphere. Our knowledge of the biomass composition of different taxa is mainly determined by our ability to sample their biomass in the wild. For groups such as plants, the use of multiple sources to estimate global biomass increases our confidence in the validity of current estimates. However, for other groups, such as terrestrial arthropods and protists, quantitative sampling of biomass is limited by technical constraints, and comprehensive data are thus lacking. Beyond specific taxa, there are entire environments for which our knowledge is very limited, namely, the deep subsurface environments such as deep aquifers and the ocean’s crust, which might hold the world largest aquifer (38). Studies in these environments are scarce, meaning that our estimates have particularly high uncertainty ranges and unknown systematic biases. Main gaps in our knowledge of these environments pertain to the distribution of biomass between the aquifer fluids and the surrounding rocks and the distribution of biomass between different microbial taxa, such as bacteria, archaea, protists, and fungi. Scientists have closely monitored the impact of humans on global biodiversity (39–41), but less attention has been given to total biomass, resulting in high uncertainty regarding the impact of humanity on the biomass of vertebrates. Our estimates for the current and prehuman biomasses of vertebrates are only a crude first step in calculating these values (SI Appendix, Prehuman Biomass). The biomass of amphibians, which are experiencing a dramatic population decline (42), remains poorly characterized. Future research could reduce the uncertainty of current estimates by sampling more environments, which will better represent the diverse biosphere on Earth. In the case of prokaryotes, some major improvements were recently realized, with global estimates of marine deep subsurface prokaryote biomass reduced by about two orders of magnitude due to an increased diversity of sampling locations (7).
+
+Identifying gaps in our knowledge could indicate areas for which further scientific exploration could have the biggest impact on our understanding of the biosphere. As a concrete example, we identify the ratio between attached to unattached cells in the deep aquifers as a major contributor to the uncertainties associated with our estimate of the biomass of bacteria, archaea, and viruses. Improving our understanding of this specific parameter could help us better constrain the global biomasses of entire domains of life. In addition to improving our reported estimates, future studies can achieve a finer categorization of taxa. For example, the biomass of parasites, which is not resolved from their hosts in this study, might be larger than the biomass of top predators in some environments (43).
+
+By providing a unified, updated, and accessible global view of the biomass of different taxa, we also aim to disseminate knowledge of the biosphere composition to a wide range of students and researchers. Our survey puts into perspective claims regarding the overarching dominance of groups such as termites and ants (44), nematodes (45), and prokaryotes (6). For example, the biomass of termites [≈0.05 Gt C (25)] is on par with that of humans but is still around an order of magnitude smaller than that of other taxa, such as fish (≈0.7 Gt C; SI Appendix, Table S15). Other groups, such as nematodes, surpass any other animal species in terms of number of individuals (SI Appendix, Fig. S2) but constitute only about 1% of the total animal biomass.
+
+The census of biomass distribution on Earth presented here is comprehensive in scope and based on synthesis of data from the recent scientific literature. The integrated dataset enables us to draw basic conclusions concerning kingdoms that dominate the biomass of the biosphere, the distribution of biomass of each kingdom across different environments, and the opposite structures of the global marine and terrestrial biomass pyramids. We identify areas in which current knowledge is lacking and further research is most required. Ideally, future research will include both temporal and geographic resolution. We believe that the results described in this study will provide students and researchers with a holistic quantitative context for studying our biosphere.
+Materials and Methods
+Taxon-Specific Detailed Description of Data Sources and Procedures for Estimating Biomass.
+
+The complete account of the data sources used for estimating the biomass of each taxon, procedures for estimating biomass, and projections for the uncertainty associated with the estimate for the biomass of each taxon are provided in the SI Appendix. To make the steps for estimating the biomass of each taxon more accessible, we provide supplementary tables that summarize the procedure as well as online notebooks for the calculation of the biomass of each taxon (see data flow scheme in SI Appendix, Overview). In Table 1, we detail the relevant supplementary table that summarizes the steps for arriving at each estimate. All of the data used to generate our estimates, as well as the code used for analysis, are open-sourced and available at https://github.com/milo-lab/biomass_distribution.
+Choice of Units for Measuring Biomass.
+
+Biomass is reported in gigatons of carbon. Alternative options to represent biomass include, among others, biovolume, wet mass, or dry weight. We chose to use carbon mass as the measure of biomass because it is independent of water content and is used extensively in the literature. Dry mass also has these features but is used less frequently. All of our reported values can be transformed to dry weight to a good approximation by multiplying by 2, the characteristic conversion factor between carbon and total dry mass (46–48).
+
+We report the significant digits for our values throughout the paper using the following scheme: For values with an uncertainty projection that is higher than twofold, we report a single significant digit. For values with an uncertainty projection of less than twofold, we report two significant digits. In cases when we report one significant digit, we do not consider a leading “1” as a significant digit.
+General Framework for Estimating Global Biomass.
+
+In achieving global estimates, there is a constant challenge of how to move from a limited set of local samples to a representative global value. How does one estimate global biomass based on a limited set of local samples? For a crude estimate, the average of all local values of biomass per unit area is multiplied by the total global area. A more effective estimate can be made by correlating measured values to environmental parameters that are known at a global scale (e.g., temperature, depth, distance from shore, primary productivity, biome type), as shown in Fig. 3. This correlation is used to extrapolate the biomass of a taxon at a specific location based on the known distribution of the environmental parameter (e.g., the temperature at each location on the globe). By integrating across the total surface of the world, a global estimate is derived. We detail the specific extrapolation procedure used for each taxon in both the SI Appendix and supplementary tables (SI Appendix, Tables S1–S23). For most taxa, our best estimates are based on a geometric mean of several independent estimates using different methodologies. The geometric mean estimates the median value if the independent estimates are log-normally distributed or, more generally, the distribution of estimates is symmetrical in log space.
+
+Uncertainty Estimation and Reporting.
+
+Global estimates such as those we use in the present work are largely based on sampling from the distribution of biomass worldwide and then extrapolating for areas in which samples are missing. The sampling of biomass in each location can be based on direct biomass measurements or conversion to biomass from other types of measurement, such as number of individuals and their characteristic weight. Some of the main sources of uncertainty for the estimates we present are the result of using such geographical extrapolations and conversion from number of individuals to overall biomass. The certainty of the estimate is linked to the amount of sampling on which the estimate is based. Notable locations in which sampling is scarce are the deep ocean (usually deeper than 200 m) and deep layers of soil (usually deeper than 1 m). For some organisms, such as annelids and marine protists and arthropods, most estimates neglect these environments, thus underestimating the actual biomass. Sampling can be biased toward places that have high abundance and diversity of wildlife. Relying on data with such sampling bias can cause overestimation of the actual biomass of a taxon.
+
+Another source of uncertainty comes from conversion to biomass. Conversion from counts of individuals to biomass is based on either known average weights per individual (e.g., 50 kg of wet weight for a human, which averages over adults and children, or 10 mg of dry weight for a “characteristic” earthworm) or empirical allometric equations that are organism-specific, such as conversion from animal length to biomass. When using such conversion methods, there is a risk of introducing biases and noise into the final estimate. Nevertheless, there is often no way around using such conversions. As such, we must be aware that the data may contain such biases.
+
+In addition to describing the procedures leading to the estimate of each taxon, we quantitatively survey the main sources of uncertainty associated with each estimate and calculate an uncertainty range for each of our biomass estimates. We choose to report uncertainties as representing, to the best of our ability given the many constraints, what is equivalent to a 95% confidence interval for the estimate of the mean. Uncertainties reported in our analysis are multiplicative (fold change from the mean) and not additive (± change of the estimate). We chose to use multiplicative uncertainty as it is more robust to large fluctuations in estimates, and because it is in accord with the way we generate our best estimates, which is usually by using a geometric mean of different independent estimates. Our uncertainty projections are focused on the main kingdoms of life: plants, bacteria, archaea, fungi, protists, and animals.
+
+The general framework for constructing our uncertainties (described in detail for each taxon in the SI Appendix and in the online notebooks) takes into account both intrastudy uncertainty and interstudy uncertainty. Intrastudy uncertainty refers to uncertainty estimates reported within a specific study, whereas interstudy uncertainty refers to variation in estimates of a certain quantity between different papers. In many cases, we use several independent methodologies to estimate the same quantity. In these cases, we can also use the variation between estimates from each methodology as a measure of the uncertainty of our final estimate. We refer to this type of uncertainty as intermethod uncertainty. The way we usually calculate uncertainties is by taking the logarithm of the values reported either within studies or from different studies. Taking the logarithm moves the values to log-space, where the SE is calculated (by dividing the SD by the square root of the number of values). We then multiply the SE by a factor of 1.96 (which would give the 95% confidence interval if the transformed data were normally distributed). Finally, we exponentiate the result to get the multiplicative factor in linear space that represents the confidence interval (akin to a 95% confidence interval if the data were log-normally distributed).
+
+Most of our estimates are constructed by combining several different estimates (e.g., combining total number of individuals and characteristic carbon content of a single organism). In these cases, we use intrastudy, interstudy, or intermethod variation associated with each parameter that is used to derive the final estimate and propagate these uncertainties to the final estimate of biomass. The uncertainty analysis for each specific biomass estimate incorporates different components of this general scheme, depending on the amount of information that is available, as detailed on a case-by-case basis in the SI Appendix.
+
+In cases where information is ample, the procedure described above yields several different uncertainty estimates for each parameter that we use to derive the final estimate (e.g., intrastudy uncertainty, interstudy uncertainty). We integrate these different uncertainties, usually by taking the highest value as the best projection of uncertainty. In some cases, for example, when information is scarce or some sources of uncertainty are hard to quantify, we base our estimates on the uncertainty in analogous taxa and consultation with relevant experts. We tend to round up our uncertainty projections when data are especially limited.
+Taxonomic Levels Used.
+
+Our census gives estimates for the global biomass at various taxonomic levels. Our main results relate to the kingdom level: animals, archaea, bacteria, fungi, plants, and protists. Although the division into kingdoms is not the most contemporary taxonomic grouping that exists, we chose to use it for the current analysis as most of the data we rely upon does not provide finer taxonomic details (e.g., the division of terrestrial protists is mainly based on morphology and not on taxonomy). We supplement these kingdoms of living organisms with an estimate for the global biomass of viruses, which are not included in the current tree of life but play a key role in global biogeochemical cycles (49). For all kingdoms except animals, all taxa making up the kingdom are considered together. For estimating the biomass of animals, we use a bottom-up approach, which estimates the biomass of key phyla constituting the animal kingdom. The sum of the biomass of these phyla represents our estimate of the total biomass of animals. We give estimates for most phyla and estimate bounds for the possible biomass contribution for the remaining phyla (SI Appendix, Other Animal Phyla). Within chordates, we provide estimates for key classes, such as fish, mammals, and birds. We estimate that the contribution of reptiles and amphibians to the total chordate biomass is negligible, as we discuss in the SI Appendix. We divide the class of mammals into wild mammals and humans plus livestock (without a contribution from poultry, which is negligible compared with cattle and pigs). Even though livestock is not a valid taxonomic division, we use it to consider the impact of humans on the total biomass of mammals.
+Data Availability
+Acknowledgments
+
+We thank Shai Meiri for help with estimating the biomass of wild mammals, birds, and reptiles and Arren Bar-Even, Oded Beja, Jorg Bernhardt, Tristan Biard, Chris Bowler, Nuno Carvalhais, Otto Coredero, Gidon Eshel, Ofer Feinerman, Noah Fierer, Daniel Fisher, Avi Flamholtz, Assaf Gal, José Grünzweig, Marcel van der Heijden, Dina Hochhauser, Julie Huber, Qusheng Jin, Bo Barker Jørgensen, Jens Kallmeyer, Tamir Klein, Christian Koerner, Daniel Madar, Fabrice Not, Katherine O’Donnell, Gal Ofir, Victoria Orphan, Noam Prywes, John Raven, Dave Savage, Einat Segev, Maya Shamir, Izak Smit, Rotem Sorek, Ofer Steinitz, Miri Tsalyuk, Assaf Vardi, Colomban de Vargas, Joshua Weitz, Yossi Yovel, Yonatan Zegman, and two anonymous reviewers for productive feedback on this manuscript. This research was supported by the European Research Council (project NOVCARBFIX 646827), the Israel Science Foundation (Grant 740/16), the ISF-NRF Singapore Joint Research Program (Grant 7662712), the Beck Canadian Center for Alternative Energy Research, Dana and Yossie Hollander, the Ullmann Family Foundation, the Helmsley Charitable Foundation, the Larson Charitable Foundation, the Wolfson Family Charitable Trust, Charles Rothschild, and Selmo Nussenbaum. This study was also supported by the NIH through Grant 1R35 GM118043-01 (MIRA). R.M. is the Charles and Louise Gartner Professional Chair.

data/news_article_1.txt

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+ 
+
+Conor McGregor will run for the Irish presidency in elections later this year, the controversial former fighter said on Thursday, as he announced his candidacy for the largely ceremonial role on an anti-immigration stance.
+
+McGregor, who in recent years has emerged as a figurehead for the far-right in Ireland, said on social media that he would run for president to oppose a long-awaited new European Union migration pact aimed at sharing the burden of processing asylum claims more evenly across the bloc.
+
+“Who else will stand up to Government and oppose this bill?” he said in an Instagram post to his more than 46 million followers. “Any other Presidential candidate they attempt to put forward will be of no resistance to them. I will!”
+
+The post comes just days after McGregor, 36, appeared at the White House with Donald Trump on St. Patrick Day, where he became the latest European ally of the US president to promote anti-immigrant sentiment – drawing controversy and censure back home.
+
+“Ireland is at the cusp of potentially losing its Irishness,” McGregor said Monday, claiming the government had “abandoned the voices” of Irish people and that rural towns were being overrun by immigrants. 
+
+Irish leader Micheál Martin said McGregor comments “did not reflect the spirit of St. Patrick Day, or the views of the people of Ireland.”
+
+ Once the face of the Ultimate Fighting Championship, Dublin-born McGregor was the first fighter to hold two UFC belts simultaneously and, according to Forbes, was the world highest paid sports star in 2021.
+
+Despite several rumored comebacks, he hasn’t fought in the UFC since back-to-back defeats four years ago – and has become a hugely controversial figure in Ireland, dogged by accusations of sexual assault, which he has denied.
+
+In a January civil lawsuit, a woman accused McGregor of sexual battery during the 2023 NBA Finals in Miami. The incident was investigated by police at the time and the Miami-Dade state attorney declined to press charges against him. McGregor said the allegations were false.
+
+Last fall, a civil jury in Dublin awarded nearly 250,000 euros ($257,000) in damages to a woman who claimed McGregor had “brutally raped and battered” her in a hotel in Dublin in 2018. McGregor testified that the two had consensual sex and vowed to appeal the verdict.
+
+In recent years, McGregor has also turned his attention to sparring with people on social media. Political analysts and far-right experts have told CNN that McGregor unique brand of Irish patriotism that won him supporters as a fighter has mutated into a strand of “far-right” Irish nationalism.
+
+As far back as 2022, McGregor had expressed support for people protesting against immigration. Some Irish politicians have accused him of fanning the flames of discontent online, voicing his anger at Ireland immigration policy – a particularly sensitive issue given the country long history of emigration.
+
+Ireland, a country of just over 5 million people, saw 141,600 immigrants arrive in the year leading up to April 2023 – the highest figure in 16 years with some attracted by its strong economic performance, according to the Central Statistics Office Ireland.
+
+ But for many ordinary workers, the benefits are failing to reach their pockets and they are struggling to afford high housing prices and rents.
+
+Ireland next presidential election must take place by November 11.
+
+In his Instagram post Thursday, McGregor said he would put the EU migration bill to a referendum if elected.
+
+“Although I oppose greatly this pact, it is neither mine nor government choice to make. It is the people of Ireland choice! Always!” he wrote.
+
+“This is the future of Ireland with me as President.”
+
+But McGregor faces an uphill task to get his name on the ballot as few Irish lawmakers share his vehement anti-immigrant views, and many publicly criticized him after the civil case last November.
+
+Presidential candidates must be nominated by at least 20 of the 234 members of the lower and upper houses of parliament or by four of Ireland 31 local councils, according to the country electoral commission.

data/news_article_2.txt

@@ -0,0 +1,31 @@
+ The government of Israel’s Prime Minister Benjamin Netanyahu has voted to dismiss Ronen Bar, the chief of Israel’s Shin Bet internal security service.
+
+The vote in the early hours of Friday local time could still be subject to appeals by Israel’s Supreme Court.
+
+“The government has now unanimously approved Prime Minister Benjamin Netanyahu’s proposal to terminate the term of Shin Bet head Ronen Bar,” the Prime Minister’s Office said in a statement Friday.
+
+“Ronen Bar will end his role as Shin Bet head on April 10, 2025, or when a permanent Shin Bet head is appointed – whichever comes first,” it added.
+
+It came after Netanyahu met with Bar last week and informed him that he would propose his removal.
+
+In a video statement released on Sunday, Netanyahu said his “ongoing distrust” of Bar had led to the move. “At all times, but especially in such an existential war, the prime minister must have full confidence in the head of the Shin Bet,” Netanyahu said.
+
+Netanyahu added that removing Bar would be necessary for achieving Israel’s war goals in Gaza and “preventing the next disaster.” The prime minister has frequently criticized the agency, placing blame on its leaders for the security lapses that led to the Hamas October 7, 2023, attacks that killed more than 1,200 people.
+
+Shin Bet, which is in charge of monitoring domestic threats to Israel, conducted an internal investigation that determined that the agency had “failed in its mission” to prevent the attacks. But it also blamed policies enacted by Netanyahu’s government as contributing factors, such as politicians’ visits to the Al Aqsa compound in Jerusalem, “the treatment of prisoners, and the perception that Israeli society has been weakened due to the damage to social cohesion.” 
+
+ An Israeli official told CNN on Thursday that the government had “lost all confidence in Ronen Bar, who continues to cling to his seat while cynically using the families of the hostages and politically improperly using his position to fabricate futile, unfounded investigations.”
+
+Shin Bet is reported to have recently opened an investigation into allegations that members of Netanyahu’s office inappropriately lobbied on behalf of Qatar – something his office denies.
+
+On Wednesday, the office of Attorney General Gali Baharav-Miara sent a letter to Netanyahu saying that the government could not fire Bar without the approval of a special committee.
+
+Netanyahu responded with a letter on Thursday, saying Baharav-Miara was “exceeding her authority” and “giving legal opinions and instructions to the government in violation of Supreme Court rulings.”
+
+Bar released a statement just hours before his dismissal saying the vote by Netanyahu’s cabinet “was hastily convened, contrary to every basic legal rule dealing with the right to be heard and contrary to the position of the legal adviser to the government.”
+
+Netanyahu has previously removed both Bar and the head of the Mossad intelligence service, David Barnea, from the negotiating team engaging in indirect talks with Hamas regarding the Gaza ceasefire and hostage deal.
+
+Opposition politicians have criticized Netanyahu’s targeting of Bar, claiming it is politically motivated.
+
+“The dismissal of the head of the service at this time, at the initiative of the prime minister, sends a message to all those involved, a message that may jeopardize the optimal outcome of the investigation. This is a direct danger to the security of the state of Israel,” Bar said in his statement Thursday.

data/wiki_car.txt

@@ -0,0 +1,120 @@
+A car, or an automobile, is a motor vehicle with wheels. Most definitions of cars state that they run primarily on roads, seat one to eight people, have four wheels, and mainly transport people rather than cargo.[1][2] There are around one billion cars in use worldwide.
+
+The French inventor Nicolas-Joseph Cugnot built the first steam-powered road vehicle in 1769, while the Swiss inventor François Isaac de Rivaz designed and constructed the first internal combustion-powered automobile in 1808. The modern car—a practical, marketable automobile for everyday use—was invented in 1886, when the German inventor Carl Benz patented his Benz Patent-Motorwagen. Commercial cars became widely available during the 20th century. The 1901 Oldsmobile Curved Dash and the 1908 Ford Model T, both American cars, are widely considered the first mass-produced[3][4] and mass-affordable[5][6][7] cars, respectively. Cars were rapidly adopted in the US, where they replaced horse-drawn carriages.[8] In Europe and other parts of the world, demand for automobiles did not increase until after World War II.[9] In the 21st century, car usage is still increasing rapidly, especially in China, India, and other newly industrialised countries.[10][11]
+
+Cars have controls for driving, parking, passenger comfort, and a variety of lamps. Over the decades, additional features and controls have been added to vehicles, making them progressively more complex. These include rear-reversing cameras, air conditioning, navigation systems, and in-car entertainment. Most cars in use in the early 2020s are propelled by an internal combustion engine, fueled by the combustion of fossil fuels. Electric cars, which were invented early in the history of the car, became commercially available in the 2000s and are predicted to cost less to buy than petrol-driven cars before 2025.[12][13] The transition from fossil fuel-powered cars to electric cars features prominently in most climate change mitigation scenarios,[14] such as Project Drawdown's 100 actionable solutions for climate change.[15]
+
+There are costs and benefits to car use. The costs to the individual include acquiring the vehicle, interest payments (if the car is financed), repairs and maintenance, fuel, depreciation, driving time, parking fees, taxes, and insurance.[16] The costs to society include maintaining roads, land-use, road congestion, air pollution, noise pollution, public health, and disposing of the vehicle at the end of its life. Traffic collisions are the largest cause of injury-related deaths worldwide.[17] Personal benefits include on-demand transportation, mobility, independence, and convenience.[18] Societal benefits include economic benefits, such as job and wealth creation from the automotive industry, transportation provision, societal well-being from leisure and travel opportunities. People's ability to move flexibly from place to place has far-reaching implications for the nature of societies.[19] 
+
+The English word car is believed to originate from Latin carrus/carrum "wheeled vehicle" or (via Old North French) Middle English carre "two-wheeled cart", both of which in turn derive from Gaulish karros "chariot".[20][21] It originally referred to any wheeled horse-drawn vehicle, such as a cart, carriage, or wagon.[22] The word also occurs in other Celtic languages.[23]
+
+"Motor car", attested from 1895, is the usual formal term in British English.[2] "Autocar", a variant likewise attested from 1895 and literally meaning "self-propelled car", is now considered archaic.[24] "Horseless carriage" is attested from 1895.[25]
+
+"Automobile", a classical compound derived from Ancient Greek autós (αὐτός) "self" and Latin mobilis "movable", entered English from French and was first adopted by the Automobile Club of Great Britain in 1897.[26] It fell out of favour in Britain and is now used chiefly in North America,[27] where the abbreviated form "auto" commonly appears as an adjective in compound formations like "auto industry" and "auto mechanic".[28][29] 
+
+In 1649, Hans Hautsch of Nuremberg built a clockwork-driven carriage.[32][33] The first steam-powered vehicle was designed by Ferdinand Verbiest, a Flemish member of a Jesuit mission in China around 1672. It was a 65-centimetre-long (26 in) scale-model toy for the Kangxi Emperor that was unable to carry a driver or a passenger.[18][34][35] It is not known with certainty if Verbiest's model was successfully built or run.[35]
+
+Nicolas-Joseph Cugnot is widely credited with building the first full-scale, self-propelled mechanical vehicle in about 1769; he created a steam-powered tricycle.[36] He also constructed two steam tractors for the French Army, one of which is preserved in the French National Conservatory of Arts and Crafts.[36] His inventions were limited by problems with water supply and maintaining steam pressure.[36] In 1801, Richard Trevithick built and demonstrated his Puffing Devil road locomotive, believed by many to be the first demonstration of a steam-powered road vehicle. It was unable to maintain sufficient steam pressure for long periods and was of little practical use.
+
+The development of external combustion (steam) engines is detailed as part of the history of the car but often treated separately from the development of true cars. A variety of steam-powered road vehicles were used during the first part of the 19th century, including steam cars, steam buses, phaetons, and steam rollers. In the United Kingdom, sentiment against them led to the Locomotive Acts of 1865.
+
+In 1807, Nicéphore Niépce and his brother Claude created what was probably the world's first internal combustion engine (which they called a Pyréolophore), but installed it in a boat on the river Saone in France.[37] Coincidentally, in 1807, the Swiss inventor François Isaac de Rivaz designed his own "de Rivaz internal combustion engine", and used it to develop the world's first vehicle to be powered by such an engine. The Niépces' Pyréolophore was fuelled by a mixture of Lycopodium powder (dried spores of the Lycopodium plant), finely crushed coal dust and resin that were mixed with oil, whereas de Rivaz used a mixture of hydrogen and oxygen.[37] Neither design was successful, as was the case with others, such as Samuel Brown, Samuel Morey, and Etienne Lenoir,[38] who each built vehicles (usually adapted carriages or carts) powered by internal combustion engines.[39]
+
+In November 1881, French inventor Gustave Trouvé demonstrated a three-wheeled car powered by electricity at the International Exposition of Electricity.[40] Although several other German engineers (including Gottlieb Daimler, Wilhelm Maybach, and Siegfried Marcus) were working on cars at about the same time, the year 1886 is regarded as the birth year of the modern car—a practical, marketable automobile for everyday use—when the German Carl Benz patented his Benz Patent-Motorwagen; he is generally acknowledged as the inventor of the car.[39][41][42]
+
+In 1879, Benz was granted a patent for his first engine, which had been designed in 1878. Many of his other inventions made the use of the internal combustion engine feasible for powering a vehicle. His first Motorwagen was built in 1885 in Mannheim, Germany. He was awarded the patent for its invention as of his application on 29 January 1886 (under the auspices of his major company, Benz & Cie., which was founded in 1883). Benz began promotion of the vehicle on 3 July 1886, and about 25 Benz vehicles were sold between 1888 and 1893, when his first four-wheeler was introduced along with a cheaper model. They also were powered with four-stroke engines of his own design. Emile Roger of France, already producing Benz engines under license, now added the Benz car to his line of products. Because France was more open to the early cars, initially more were built and sold in France through Roger than Benz sold in Germany. In August 1888, Bertha Benz, the wife and business partner of Carl Benz, undertook the first road trip by car, to prove the road-worthiness of her husband's invention.[43]
+
+In 1896, Benz designed and patented the first internal-combustion flat engine, called boxermotor. During the last years of the 19th century, Benz was the largest car company in the world with 572 units produced in 1899 and, because of its size, Benz & Cie., became a joint-stock company. The first motor car in central Europe and one of the first factory-made cars in the world, was produced by Czech company Nesselsdorfer Wagenbau (later renamed to Tatra) in 1897, the Präsident automobil.
+
+Daimler and Maybach founded Daimler Motoren Gesellschaft (DMG) in Cannstatt in 1890, and sold their first car in 1892 under the brand name Daimler. It was a horse-drawn stagecoach built by another manufacturer, which they retrofitted with an engine of their design. By 1895, about 30 vehicles had been built by Daimler and Maybach, either at the Daimler works or in the Hotel Hermann, where they set up shop after disputes with their backers. Benz, Maybach, and the Daimler team seem to have been unaware of each other's early work. They never worked together; by the time of the merger of the two companies, Daimler and Maybach were no longer part of DMG. Daimler died in 1900 and later that year, Maybach designed an engine named Daimler-Mercedes that was placed in a specially ordered model built to specifications set by Emil Jellinek. This was a production of a small number of vehicles for Jellinek to race and market in his country. Two years later, in 1902, a new model DMG car was produced and the model was named Mercedes after the Maybach engine, which generated 35 hp. Maybach quit DMG shortly thereafter and opened a business of his own. Rights to the Daimler brand name were sold to other manufacturers.
+
+In 1890, Émile Levassor and Armand Peugeot of France began producing vehicles with Daimler engines, and so laid the foundation of the automotive industry in France. In 1891, Auguste Doriot and his Peugeot colleague Louis Rigoulot completed the longest trip by a petrol-driven vehicle when their self-designed and built Daimler powered Peugeot Type 3 completed 2,100 kilometres (1,300 mi) from Valentigney to Paris and Brest and back again. They were attached to the first Paris–Brest–Paris bicycle race, but finished six days after the winning cyclist, Charles Terront.
+
+The first design for an American car with a petrol internal combustion engine was made in 1877 by George Selden of Rochester, New York. Selden applied for a patent for a car in 1879, but the patent application expired because the vehicle was never built. After a delay of 16 years and a series of attachments to his application, on 5 November 1895, Selden was granted a US patent (U.S. patent 549,160) for a two-stroke car engine, which hindered, more than encouraged, development of cars in the United States. His patent was challenged by Henry Ford and others, and overturned in 1911.
+
+In 1893, the first running, petrol-driven American car was built and road-tested by the Duryea brothers of Springfield, Massachusetts. The first public run of the Duryea Motor Wagon took place on 21 September 1893, on Taylor Street in Metro Center Springfield.[44][45] Studebaker, subsidiary of a long-established wagon and coach manufacturer, started to build cars in 1897[46]: 66  and commenced sales of electric vehicles in 1902 and petrol vehicles in 1904.[47]
+
+In Britain, there had been several attempts to build steam cars with varying degrees of success, with Thomas Rickett even attempting a production run in 1860.[48] Santler from Malvern is recognised by the Veteran Car Club of Great Britain as having made the first petrol-driven car in the country in 1894,[49] followed by Frederick William Lanchester in 1895, but these were both one-offs.[49] The first production vehicles in Great Britain came from the Daimler Company, a company founded by Harry J. Lawson in 1896, after purchasing the right to use the name of the engines. Lawson's company made its first car in 1897, and they bore the name Daimler.[49]
+
+In 1892, German engineer Rudolf Diesel was granted a patent for a "New Rational Combustion Engine". In 1897, he built the first diesel engine.[39] Steam-, electric-, and petrol-driven vehicles competed for a few decades, with petrol internal combustion engines achieving dominance in the 1910s. Although various pistonless rotary engine designs have attempted to compete with the conventional piston and crankshaft design, only Mazda's version of the Wankel engine has had more than very limited success. All in all, it is estimated that over 100,000 patents created the modern automobile and motorcycle.[50] 
+
+Large-scale, production-line manufacturing of affordable cars was started by Ransom Olds in 1901 at his Oldsmobile factory in Lansing, Michigan, and based upon stationary assembly line techniques pioneered by Marc Isambard Brunel at the Portsmouth Block Mills, England, in 1802. The assembly line style of mass production and interchangeable parts had been pioneered in the US by Thomas Blanchard in 1821, at the Springfield Armory in Springfield, Massachusetts.[51] This concept was greatly expanded by Henry Ford, beginning in 1913 with the world's first moving assembly line for cars at the Highland Park Ford Plant.
+
+As a result, Ford's cars came off the line in 15-minute intervals, much faster than previous methods, increasing productivity eightfold, while using less manpower (from 12.5 manhours to 1 hour 33 minutes).[52] It was so successful, paint became a bottleneck. Only Japan black would dry fast enough, forcing the company to drop the variety of colours available before 1913, until fast-drying Duco lacquer was developed in 1926. This is the source of Ford's apocryphal remark, "any color as long as it's black".[52] In 1914, an assembly line worker could buy a Model T with four months' pay.[52]
+
+Ford's complex safety procedures—especially assigning each worker to a specific location instead of allowing them to roam about—dramatically reduced the rate of injury.[53] The combination of high wages and high efficiency is called "Fordism" and was copied by most major industries. The efficiency gains from the assembly line also coincided with the economic rise of the US. The assembly line forced workers to work at a certain pace with very repetitive motions which led to more output per worker while other countries were using less productive methods.
+
+In the automotive industry, its success was dominating, and quickly spread worldwide seeing the founding of Ford France and Ford Britain in 1911, Ford Denmark 1923, Ford Germany 1925; in 1921, Citroën was the first native European manufacturer to adopt the production method. Soon, companies had to have assembly lines, or risk going bankrupt; by 1930, 250 companies which did not, had disappeared.[52]
+
+Development of automotive technology was rapid, due in part to the hundreds of small manufacturers competing to gain the world's attention. Key developments included electric ignition and the electric self-starter (both by Charles Kettering, for the Cadillac Motor Company in 1910–1911), independent suspension, and four-wheel brakes.
+
+Since the 1920s, nearly all cars have been mass-produced to meet market needs, so marketing plans often have heavily influenced car design. It was Alfred P. Sloan who established the idea of different makes of cars produced by one company, called the General Motors Companion Make Program, so that buyers could "move up" as their fortunes improved.
+
+Reflecting the rapid pace of change, makes shared parts with one another so larger production volume resulted in lower costs for each price range. For example, in the 1930s, LaSalles, sold by Cadillac, used cheaper mechanical parts made by Oldsmobile; in the 1950s, Chevrolet shared bonnet, doors, roof, and windows with Pontiac; by the 1990s, corporate powertrains and shared platforms (with interchangeable brakes, suspension, and other parts) were common. Even so, only major makers could afford high costs, and even companies with decades of production, such as Apperson, Cole, Dorris, Haynes, or Premier, could not manage: of some two hundred American car makers in existence in 1920, only 43 survived in 1930, and with the Great Depression, by 1940, only 17 of those were left.[52]
+
+In Europe, much the same would happen. Morris set up its production line at Cowley in 1924, and soon outsold Ford, while beginning in 1923 to follow Ford's practice of vertical integration, buying Hotchkiss' British subsidiary (engines), Wrigley (gearboxes), and Osberton (radiators), for instance, as well as competitors, such as Wolseley: in 1925, Morris had 41 per cent of total British car production. Most British small-car assemblers, from Abbey to Xtra, had gone under. Citroën did the same in France, coming to cars in 1919; between them and other cheap cars in reply such as Renault's 10CV and Peugeot's 5CV, they produced 550,000 cars in 1925, and Mors, Hurtu, and others could not compete.[52] Germany's first mass-manufactured car, the Opel 4PS Laubfrosch (Tree Frog), came off the line at Rüsselsheim in 1924, soon making Opel the top car builder in Germany, with 37.5 per cent of the market.[52]
+
+In Japan, car production was very limited before World War II. Only a handful of companies were producing vehicles in limited numbers, and these were small, three-wheeled for commercial uses, like Daihatsu, or were the result of partnering with European companies, like Isuzu building the Wolseley A-9 in 1922. Mitsubishi was also partnered with Fiat and built the Mitsubishi Model A based on a Fiat vehicle. Toyota, Nissan, Suzuki, Mazda, and Honda began as companies producing non-automotive products before the war, switching to car production during the 1950s. Kiichiro Toyoda's decision to take Toyoda Loom Works into automobile manufacturing would create what would eventually become Toyota Motor Corporation, the largest automobile manufacturer in the world. Subaru, meanwhile, was formed from a conglomerate of six companies who banded together as Fuji Heavy Industries, as a result of having been broken up under keiretsu legislation. 
+
+Fossil fuels
+
+Most cars in use in the early 2020s run on petrol burnt in an internal combustion engine (ICE). Some cities ban older more polluting petrol-driven cars and some countries plan to ban sales in future. However, some environmental groups say this phase-out of fossil fuel vehicles must be brought forwards to limit climate change. Production of petrol-fuelled cars peaked in 2017.[55][56]
+
+Other hydrocarbon fossil fuels also burnt by deflagration (rather than detonation) in ICE cars include diesel, autogas, and CNG. Removal of fossil fuel subsidies,[57][58] concerns about oil dependence, tightening environmental laws and restrictions on greenhouse gas emissions are propelling work on alternative power systems for cars. This includes hybrid vehicles, plug-in electric vehicles and hydrogen vehicles. Out of all cars sold in 2021, nine per cent were electric, and by the end of that year there were more than 16 million electric cars on the world's roads.[59] Despite rapid growth, less than two per cent of cars on the world's roads were fully electric and plug-in hybrid cars by the end of 2021.[59] Cars for racing or speed records have sometimes employed jet or rocket engines, but these are impractical for common use. Oil consumption has increased rapidly in the 20th and 21st centuries because there are more cars; the 1980s oil glut even fuelled the sales of low-economy vehicles in OECD countries. The BRIC countries are adding to this consumption.
+Batteries
+Main article: Electric vehicle battery
+See also: Electric car § Batteries, and Automotive battery
+
+In almost all hybrid (even mild hybrid) and pure electric cars regenerative braking recovers and returns to a battery some energy which would otherwise be wasted by friction brakes getting hot.[60] Although all cars must have friction brakes (front disc brakes and either disc or drum rear brakes[61]) for emergency stops, regenerative braking improves efficiency, particularly in city driving.[62] 
+
+Cars are equipped with controls used for driving, passenger comfort, and safety, normally operated by a combination of the use of feet and hands, and occasionally by voice on 21st-century cars. These controls include a steering wheel, pedals for operating the brakes and controlling the car's speed (and, in a manual transmission car, a clutch pedal), a shift lever or stick for changing gears, and a number of buttons and dials for turning on lights, ventilation, and other functions. Modern cars' controls are now standardised, such as the location for the accelerator and brake, but this was not always the case. Controls are evolving in response to new technologies, for example, the electric car and the integration of mobile communications.
+
+Some of the original controls are no longer required. For example, all cars once had controls for the choke valve, clutch, ignition timing, and a crank instead of an electric starter. However, new controls have also been added to vehicles, making them more complex. These include air conditioning, navigation systems, and in-car entertainment. Another trend is the replacement of physical knobs and switches by secondary controls with touchscreen controls such as BMW's iDrive and Ford's MyFord Touch. Another change is that while early cars' pedals were physically linked to the brake mechanism and throttle, in the early 2020s, cars have increasingly replaced these physical linkages with electronic controls. 
+
+Cars are typically equipped with interior lighting which can be toggled manually or be set to light up automatically with doors open, an entertainment system which originated from car radios, sideways windows which can be lowered or raised electrically (manually on earlier cars), and one or multiple auxiliary power outlets for supplying portable appliances such as mobile phones, portable fridges, power inverters, and electrical air pumps from the on-board electrical system.[63][64][a] More costly upper-class and luxury cars are equipped with features earlier such as massage seats and collision avoidance systems.[65][66]
+
+Cars are typically fitted with multiple types of lights. These include headlights, which are used to illuminate the way ahead and make the car visible to other users, so that the vehicle can be used at night; in some jurisdictions, daytime running lights; red brake lights to indicate when the brakes are applied; amber turn signal lights to indicate the turn intentions of the driver; white-coloured reverse lights to illuminate the area behind the car (and indicate that the driver will be or is reversing); and on some vehicles, additional lights (e.g., side marker lights) to increase the visibility of the car. Interior lights on the ceiling of the car are usually fitted for the driver and passengers. Some vehicles also have a boot light and, more rarely, an engine compartment light. 
+
+During the late 20th and early 21st century, cars increased in weight due to batteries,[68] modern steel safety cages, anti-lock brakes, airbags, and "more-powerful—if more efficient—engines"[69] and, as of 2019, typically weigh between 1 and 3 tonnes (1.1 and 3.3 short tons; 0.98 and 2.95 long tons).[70] Heavier cars are safer for the driver from a crash perspective, but more dangerous for other vehicles and road users.[69] The weight of a car influences fuel consumption and performance, with more weight resulting in increased fuel consumption and decreased performance. The Wuling Hongguang Mini EV, a typical city car, weighs about 700 kilograms (1,500 lb). Heavier cars include SUVs and extended-length SUVs like the Suburban. Cars have also become wider.[71]
+
+Some places tax heavier cars more:[72] as well as improving pedestrian safety this can encourage manufacturers to use materials such as recycled aluminium instead of steel.[73] It has been suggested that one benefit of subsidising charging infrastructure is that cars can use lighter batteries.[74] 
+
+Most cars are designed to carry multiple occupants, often with four or five seats. Cars with five seats typically seat two passengers in the front and three in the rear. Full-size cars and large sport utility vehicles can often carry six, seven, or more occupants depending on the arrangement of the seats. On the other hand, sports cars are most often designed with only two seats. Utility vehicles like pickup trucks, combine seating with extra cargo or utility functionality. The differing needs for passenger capacity and their luggage or cargo space has resulted in the availability of a large variety of body styles to meet individual consumer requirements that include, among others, the sedan/saloon, hatchback, station wagon/estate, coupe, and minivan. 
+
+Traffic collisions are the largest cause of injury-related deaths worldwide.[17] Mary Ward became one of the first documented car fatalities in 1869 in Parsonstown, Ireland,[75] and Henry Bliss one of the US's first pedestrian car casualties in 1899 in New York City.[76] There are now standard tests for safety in new cars, such as the Euro and US NCAP tests,[77] and insurance-industry-backed tests by the Insurance Institute for Highway Safety (IIHS).[78] However, not all such tests consider the safety of people outside the car, such as drivers of other cars, pedestrians and cyclists.[79]
+
+The costs of car usage, which may include the cost of: acquiring the vehicle, repairs and auto maintenance, fuel, depreciation, driving time, parking fees, taxes, and insurance,[16] are weighed against the cost of the alternatives, and the value of the benefits—perceived and real—of vehicle usage. The benefits may include on-demand transportation, mobility, independence, and convenience,[18] and emergency power.[81] During the 1920s, cars had another benefit: "[c]ouples finally had a way to head off on unchaperoned dates, plus they had a private space to snuggle up close at the end of the night."[82]
+
+Similarly the costs to society of car use may include; maintaining roads, land use, air pollution, noise pollution, road congestion, public health, health care, and of disposing of the vehicle at the end of its life; and can be balanced against the value of the benefits to society that car use generates. Societal benefits may include: economy benefits, such as job and wealth creation, of car production and maintenance, transportation provision, society wellbeing derived from leisure and travel opportunities, and revenue generation from the tax opportunities. The ability of humans to move flexibly from place to place has far-reaching implications for the nature of societies.[19] 
+
+Car production and use has a large number of environmental impacts: it causes local air pollution plastic pollution and contributes to greenhouse gas emissions and climate change.[85] Cars and vans caused 10% of energy-related carbon dioxide emissions in 2022.[86] As of 2023, electric cars produce about half the emissions over their lifetime as diesel and petrol cars. This is set to improve as countries produce more of their electricity from low-carbon sources.[87] Cars consume almost a quarter of world oil production as of 2019.[55] Cities planned around cars are often less dense, which leads to further emissions, as they are less walkable for instance.[85] A growing demand for large SUVs is driving up emissions from cars.[88]
+
+Cars are a major cause of air pollution,[89] which stems from exhaust gas in diesel and petrol cars and from dust from brakes, tyres, and road wear. Electric cars do not produce tailpipe emissions, but are generally heavier and therefore produce slightly more particulate matter.[90] Heavy metals and microplastics (from tyres) are also released into the environment, during production, use and at the end of life. Mining related to car manufacturing and oil spills both cause water pollution.[85]
+
+Animals and plants are often negatively affected by cars via habitat destruction and fragmentation from the road network and pollution. Animals are also killed every year on roads by cars, referred to as roadkill.[85] More recent road developments are including significant environmental mitigation in their designs, such as green bridges (designed to allow wildlife crossings) and creating wildlife corridors.
+
+Governments use fiscal policies, such as road tax, to discourage the purchase and use of more polluting cars;[91] Vehicle emission standards ban the sale of new highly pollution cars.[92] Many countries plan to stop selling fossil cars altogether between 2025 and 2050.[93] Various cities have implemented low-emission zones, banning old fossil fuel and Amsterdam is planning to ban fossil fuel cars completely.[94][95] Some cities make it easier for people to choose other forms of transport, such as cycling.[94] Many Chinese cities limit licensing of fossil fuel cars,[96] 
+
+Mass production of personal motor vehicles in the United States and other developed countries with extensive territories such as Australia, Argentina, and France vastly increased individual and group mobility and greatly increased and expanded economic development in urban, suburban, exurban and rural areas.[citation needed] Growth in the popularity of cars and commuting has led to traffic congestion.[97] Moscow, Istanbul, Bogotá, Mexico City and São Paulo were the world's most congested cities in 2018 according to INRIX, a data analytics company.[98]
+Access to cars
+
+In the United States, the transport divide and car dependency resulting from domination of car-based transport systems presents barriers to employment in low-income neighbourhoods,[99] with many low-income individuals and families forced to run cars they cannot afford in order to maintain their income.[100] Dependency on automobiles by African Americans may result in exposure to the hazards of driving while black and other types of racial discrimination related to buying, financing and insuring them.[101]
+Health impact
+Further information: Motor vehicle pollution and pregnancy
+
+Air pollution from cars increases the risk of lung cancer and heart disease. It can also harm pregnancies: more children are born too early or with lower birth weight.[85] Children are extra vulnerable to air pollution, as their bodies are still developing and air pollution in children is linked to the development of asthma, childhood cancer, and neurocognitive issues such as autism.[102][85] The growth in popularity of the car allowed cities to sprawl, therefore encouraging more travel by car, resulting in inactivity and obesity, which in turn can lead to increased risk of a variety of diseases.[103] When places are designed around cars, children have fewer opportunities to go places by themselves, and lose opportunities to become more independent.[104][85]
+Emerging car technologies
+
+Although intensive development of conventional battery electric vehicles is continuing into the 2020s,[105] other car propulsion technologies that are under development include wireless charging,[106] hydrogen cars,[107][108] and hydrogen/electric hybrids.[109] Research into alternative forms of power includes using ammonia instead of hydrogen in fuel cells.[110]
+
+New materials which may replace steel car bodies include aluminium,[111] fiberglass, carbon fiber, biocomposites, and carbon nanotubes.[112] Telematics technology is allowing more and more people to share cars, on a pay-as-you-go basis, through car share and carpool schemes. Communication is also evolving due to connected car systems.[113] Open-source cars are not widespread.[114] 
+
+Fully autonomous vehicles, also known as driverless cars, already exist as robotaxis[115][116] but have a long way to go before they are in general use.[117]
+
+Car-share arrangements and carpooling are also increasingly popular, in the US and Europe.[118] For example, in the US, some car-sharing services have experienced double-digit growth in revenue and membership growth between 2006 and 2007. Services like car sharing offer residents to "share" a vehicle rather than own a car in already congested neighbourhoods.[119]
+
+The automotive industry designs, develops, manufactures, markets, and sells the world's motor vehicles, more than three-quarters of which are cars. In 2020, there were 56 million cars manufactured worldwide,[120] down from 67 million the previous year.[121] The automotive industry in China produces by far the most (20 million in 2020), followed by Japan (seven million), then Germany, South Korea and India.[122] The largest market is China, followed by the US.
+
+Around the world, there are about a billion cars on the road;[123] they burn over a trillion litres (0.26×1012 US gal; 0.22×1012 imp gal) of petrol and diesel fuel yearly, consuming about 50 exajoules (14,000 TWh) of energy.[124] The numbers of cars are increasing rapidly in China and India.[125] In the opinion of some, urban transport systems based around the car have proved unsustainable, consuming excessive energy, affecting the health of populations, and delivering a declining level of service despite increasing investment. Many of these negative effects fall disproportionately on those social groups who are also least likely to own and drive cars.[126][127] The sustainable transport movement focuses on solutions to these problems. The car industry is also facing increasing competition from the public transport sector, as some people re-evaluate their private vehicle usage. In July 2021, the European Commission introduced the "Fit for 55" legislation package, outlining crucial directives for the automotive sector's future.[128][129] According to this package, by 2035, all newly sold cars in the European market must be Zero-emissions vehicles.[130][131][132] 
+
+Established alternatives for some aspects of car use include public transport such as busses, trolleybusses, trains, subways, tramways, light rail, cycling, and walking. Bicycle sharing systems have been established in China and many European cities, including Copenhagen and Amsterdam. Similar programmes have been developed in large US cities.[133][134] Additional individual modes of transport, such as personal rapid transit could serve as an alternative to cars if they prove to be socially accepted.[135] A study which checked the costs and the benefits of introducing Low Traffic Neighbourhood in London found the benefits overpass the costs approximately by 100 times in the first 20 years and the difference is growing over time.[136]

data/wiki_dog.txt

@@ -0,0 +1,22 @@
+Dogs are mammals, usually to be kept as pets, for work on farms or for the police. Some dogs are trained to be rescue dogs and join teams such as mountain rescue.[4]
+
+They have been bred by humans from ancestral wolves. They were the first animal to live with humans.[5]
+
+There was a lot of different types among wolves in the Late Pleistocene.[1] The dingo is also a dog, but many dingos have become wild animals again and live in the wild, away from humans (parts of Australia).[6]
+
+Today, some dogs are used as pets, and others are used to help humans do their work. They are popular pets because they are usually playful, friendly, loyal, and listen to humans. Thirty million dogs in the United States have been registered as pets.[7] Dogs eat both meat and vegetables. Often mixed together and sold in stores as dog food.[8] Dogs often have jobs including police dogs, army dogs, assistance dogs, fire dogs, messenger dogs, hunting dogs, herding dogs, or rescue dogs. They are sometimes called "canines" from the Latin word for dog - canis. Wolves are also canines. A baby dog is called a pup or puppy. A dog is called a puppy until it is about one year old.[9]
+
+Dogs are sometimes known as "human's best friend" because they are kept as pets, are usually loyal, and like being around humans. Dogs like to be petted, but only when they can first see the petter's hand before petting. One should never pet a dog from behind.[10]
+
+August 26 is National Dog Day worldwide.[11] While March 26 is National Puppy Day in the United States.[12]
+Appearance and behaviour
+
+Dogs can smell and hear better than humans but cannot see well in color because they are color blind. Due to the structure of the eye, dogs can see better in low light than humans. They also have a larger field of vision.[13]
+
+Like wolves, wild dogs travel in groups called packs. Packs of dogs are listed by rank, and dogs with low rank will submit to other dogs with a higher rank. The highest ranked dog is called the alpha male. A dog in a group helps and cares for others. Pet dogs often view their owner as the alpha male.[14] 
+
+Different dog breeds have different lifespans. In general, smaller dogs live longer than bigger ones.[15] The size and the breed of the dog change how long the dog lives on average. Breeds such as the Dachshund usually live for fifteen years, Chihuahuas can reach age of twenty. On the other hand, the Great Dane has an average lifespan of six to eight years; some Great Danes have lived for as long as ten years. An American Bulldog lives for around 15 years. Bigger dogs will have smaller lives than smaller dogs because of the pressure on its heart to move around.[16]
+
+Dogs are often called "man's best friend" because they fit in with human life. Dogs can serve people in many ways. For example, there are guard dogs, hunting dogs, herding dogs, guide dogs for blind people, and police dogs. There are also dogs that are trained to smell for diseases in the human body or to find bombs or illegal drugs. These dogs sometimes help police in airports or other areas. Sniffer dogs (usually beagles) are sometimes trained for this job. Dogs have even been sent by Russians into outer space, a few years before any human being. The first dog sent up was named Laika, but she died within a few hours.[17]
+
+There is much more variety in dogs than in cats. That is mainly because of the way humans have selected and bred dogs for specific jobs and functions. It may also have something to do with the fact that dogs are pack animals, whereas cats are not.[18] 

scrape.sh

@@ -1,9 +0,0 @@
-#!/bin/bash
-
-FILE_PATH="./words.txt"
-
-while read -r line; do
-	for (( i=0; i<${#line}; i++ )); do
-		printf "%d-" "'${line:$i:1}"
-	done
-done < "$FILE_PATH"

transform.sh

@@ -0,0 +1,35 @@
+#!/bin/bash
+
+FILE_PATH="./words.txt"
+
+vowels="aeiouy"
+
+while read -r line; do
+	prev=""
+	prevprev=""
+
+	for (( i=0; i<${#line}; i++ )); do
+		curr="${line:$i:1}"
+
+		curr_lower=$(echo "$curr" | tr 'A-Z' 'a-z')
+		prev_lower=$(echo "$prev" | tr 'A-Z' 'a-z')
+		prevprev_lower=$(echo "$prevprev" | tr 'A-Z' 'a-z')
+
+		curr_val=$(printf "%d" "'$curr_lower")
+		prev_val=0
+		prevprev_val=0
+
+		if [ -n "$prev_lower" ]; then
+			prev_val=$(printf "%d" "'$prev_lower")
+		fi
+		if [ -n "$prevprev_lower" ]; then
+			prevprev_val=$(printf "%d" "'$prevprev_lower")
+		fi
+
+		printf "%d-%d-%d " "$prevprev_val" "$prev_val" "$curr_val"
+
+		prevprev="$prev"
+		prev="$curr"
+	done
+	echo
+done < "$FILE_PATH"

words.sh

@@ -0,0 +1,4 @@
+#!/bin/bash
+
+
+grep -o "[[:alpha:]]\{1,\}" "$1" | tr '[:upper:]' '[:lower:]'

words.txt

@@ -1,996 +0,0 @@
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-I
-his
-that
-he
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-one
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-by
-hot
-word
-but
-what
-some
-is
-it
-you
-or
-had
-the
-of
-to
-and
-a
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-we
-can
-out
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-were
-which
-do
-their
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-if
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-how
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-an
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-does
-set
-three
-want
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-also
-play
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-end
-put
-home
-read
-hand
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-spell
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-even
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-here
-must
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-such
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-act
-why
-ask
-men
-change
-went
-light
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-need
-house
-picture
-try
-us
-again
-animal
-point
-mother
-world
-near
-build
-self
-earth
-father
-any
-new
-work
-part
-take
-get
-place
-made
-live
-where
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-back
-little
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-year
-came
-show
-every
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-give
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-just
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-great
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-say
-help
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-line
-differ
-turn
-cause
-much
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-move
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-boy
-old
-too
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-she
-all
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-up
-use
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-about
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-would
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-her
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-day
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-number
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-no
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-know
-water
-than
-call
-first
-who
-may
-down
-side
-been
-now
-find
-head
-stand
-own
-page
-should
-country
-found
-answer
-school
-grow
-study
-still
-learn
-plant
-cover
-food
-sun
-four
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-state
-keep
-eye
-never
-last
-let
-thought
-city
-tree
-cross
-farm
-hard
-start
-might
-story
-saw
-far
-sea
-draw
-left
-late
-run
-while
-press
-close
-night
-real
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-few
-north
-book
-carry
-took
-science
-eat
-room
-friend
-began
-idea
-fish
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-stop
-once
-base
-hear
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-cut
-sure
-watch
-color
-face
-wood
-main
-open
-seem
-together
-next
-white
-children
-begin
-got
-walk
-example
-ease
-paper
-group
-always
-music
-those
-both
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-often
-letter
-until
-mile
-river
-car
-feet
-care
-second
-enough
-plain
-girl
-usual
-young
-ready
-above
-ever
-red
-list
-though
-feel
-talk
-bird
-soon
-body
-dog
-family
-direct
-pose
-leave
-song
-measure
-door
-product
-black
-short
-numeral
-class
-wind
-question
-happen
-complete
-ship
-area
-half
-rock
-order
-fire
-south
-problem
-piece
-told
-knew
-pass
-since
-top
-whole
-king
-street
-inch
-multiply
-nothing
-course
-stay
-wheel
-full
-force
-blue
-object
-decide
-surface
-deep
-moon
-island
-foot
-system
-busy
-test
-record
-boat
-common
-gold
-possible
-plane
-stead
-dry
-wonder
-laugh
-thousand
-ago
-ran
-check
-game
-shape
-equate
-miss
-brought
-heat
-snow
-tire
-bring
-yes
-distant
-fill
-east
-paint
-language
-among
-unit
-power
-town
-fine
-certain
-fly
-fall
-lead
-cry
-dark
-machine
-note
-wait
-plan
-figure
-star
-box
-noun
-field
-rest
-correct
-able
-pound
-done
-beauty
-drive
-stood
-contain
-front
-teach
-week
-final
-gave
-green
-oh
-quick
-develop
-ocean
-warm
-free
-minute
-strong
-special
-mind
-behind
-clear
-tail
-produce
-fact
-space
-heard
-best
-hour
-better
-true
-during
-hundred
-five
-remember
-step
-early
-hold
-west
-ground
-interest
-reach
-fast
-verb
-sing
-listen
-six
-table
-travel
-less
-morning
-ten
-simple
-several
-vowel
-toward
-war
-lay
-against
-pattern
-slow
-center
-love
-person
-money
-serve
-appear
-road
-map
-rain
-rule
-govern
-pull
-cold
-notice
-voice
-energy
-hunt
-probable
-bed
-brother
-egg
-ride
-cell
-believe
-perhaps
-pick
-sudden
-count
-square
-reason
-length
-represent
-art
-subject
-region
-size
-vary
-settle
-speak
-weight
-general
-ice
-matter
-circle
-pair
-include
-divide
-syllable
-felt
-grand
-ball
-yet
-wave
-drop
-heart
-am
-present
-heavy
-dance
-engine
-position
-arm
-wide
-sail
-material
-fraction
-forest
-sit
-race
-window
-store
-summer
-train
-sleep
-prove
-lone
-leg
-exercise
-wall
-catch
-mount
-wish
-sky
-board
-joy
-winter
-sat
-written
-wild
-instrument
-kept
-glass
-grass
-cow
-job
-edge
-sign
-visit
-past
-soft
-fun
-bright
-gas
-weather
-month
-million
-bear
-finish
-happy
-hope
-flower
-clothe
-strange
-gone
-trade
-melody
-trip
-office
-receive
-row
-mouth
-exact
-symbol
-die
-least
-trouble
-shout
-except
-wrote
-seed
-tone
-join
-suggest
-clean
-break
-lady
-yard
-rise
-bad
-blow
-oil
-blood
-touch
-grew
-cent
-mix
-team
-wire
-cost
-lost
-brown
-wear
-garden
-equal
-sent
-choose
-fell
-fit
-flow
-fair
-bank
-collect
-save
-control
-decimal
-ear
-else
-quite
-broke
-case
-middle
-kill
-son
-lake
-moment
-scale
-loud
-spring
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-child
-straight
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-dictionary
-milk
-speed
-method
-organ
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-age
-section
-dress
-cloud
-surprise
-quiet
-stone
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-climb
-cool
-design
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-experiment
-bottom
-key
-iron
-single
-stick
-flat
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-smile
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-hole
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-whether
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-seven
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-describe
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-share
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-degree
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-event
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-deal
-swim
-term
-opposite
-wife
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-arrange
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-quart
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-noise
-level
-chance
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-shop
-stretch
-throw
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-property
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-molecule
-select
-wrong
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-repeat
-require
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-salt
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