Thomas A. Alspaugh
GNU Free Documentation License
Version 1.3, 3 November 2008

Under Construction

Hide/show notes
Hide/show §¶s
Automatically ¶-§-sentence numbered throughout.

Source: GNU text (2009Nov22)

Words, repeated phrases.

¶1¶1ṣ1Copyright (c) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. <>

¶2¶2ṣ1Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.


§0¶1§0¶1ṣ1The purpose of this License is to make a manual, textbook, or other functional and useful document free in the sense of freedom: ṣ1.1to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or noncommercially. §0¶1ṣ2Secondarily, this License preserves for the author and publisher a way to get credit for their work, while not being considered responsible for modifications made by others.

§0¶2§0¶2ṣ1This License is a kind of copyleft, which means that derivative works of the document must themselves be free in the same sense. §0¶2ṣ2It complements the GNU General Public License, which is a copyleft license designed for free software.

§0¶3§0¶3ṣ1We have designed this License in order to use it for manuals for free software, because free software needs free documentation: ṣ1.1a free program should come with manuals providing the same freedoms that the software does. §0¶3ṣ2But this License is not limited to software manuals; ṣ2.1it can be used for any textual work, regardless of subject matter or whether it is published as a printed book. §0¶3ṣ3We recommend this License principally for works whose purpose is instruction or reference.


§1¶1§1¶1ṣ1This License applies to any manual or other work, in any medium, that contains a notice placed by the copyright holder saying it can be distributed under the terms of this License. §1¶1ṣ2Such a notice grants a world-wide, royalty-free license, unlimited in duration, to use that work under the conditions stated herein. §1¶1ṣ3The Document, below, refers to any such manual or work. §1¶1ṣ4Any member of the public is a licensee, and is addressed as you. §1¶1ṣ5You accept the license if you copy, modify or distribute the work in a way requiring permission under copyright law.

§1¶2§1¶2ṣ1A Modified Version of the Document means any work containing the Document or a portion of it, either copied verbatim, or with modifications and/or translated into another language.

§1¶3§1¶3ṣ1A Secondary Section is a named appendix or a front-matter section of the Document that deals exclusively with the relationship of the publishers or authors of the Document to the Document's overall subject (or to related matters) and contains nothing that could fall directly within that overall subject. §1¶3ṣ2(Thus, if the Document is in part a textbook of mathematics, a Secondary Section may not explain any mathematics.) §1¶3ṣ3The relationship could be a matter of historical connection with the subject or with related matters, or of legal, commercial, philosophical, ethical or political position regarding them.

§1¶4§1¶4ṣ1The Invariant Sections are certain Secondary Sections whose titles are designated, as being those of Invariant Sections, in the notice that says that the Document is released under this License. §1¶4ṣ2If a section does not fit the above definition of Secondary then it is not allowed to be designated as Invariant. §1¶4ṣ3The Document may contain zero Invariant Sections. §1¶4ṣ4If the Document does not identify any Invariant Sections then there are none.

§1¶5§1¶5ṣ1The Cover Texts are certain short passages of text that are listed, as Front-Cover Texts or Back-Cover Texts, in the notice that says that the Document is released under this License. §1¶5ṣ2A Front-Cover Text may be at most 5 words, and a Back-Cover Text may be at most 25 words.

§1¶6§1¶6ṣ1A Transparent copy of the Document means a machine-readable copy, represented in a format whose specification is available to the general public, that is suitable for revising the document straightforwardly with generic text editors or (for images composed of pixels) generic paint programs or (for drawings) some widely available drawing editor, and that is suitable for input to text formatters or for automatic translation to a variety of formats suitable for input to text formatters. §1¶6ṣ2A copy made in an otherwise Transparent file format whose markup, or absence of markup, has been arranged to thwart or discourage subsequent modification by readers is not Transparent. §1¶6ṣ3An image format is not Transparent if used for any substantial amount of text. §1¶6ṣ4A copy that is not Transparent is called Opaque.

§1¶7§1¶7ṣ1Examples of suitable formats for Transparent copies include plain ASCII without markup, Texinfo input format, LaTeX input format, SGML or XML using a publicly available DTD, and standard-conforming simple HTML, PostScript or PDF designed for human modification. §1¶7ṣ2Examples of transparent image formats include PNG, XCF and JPG. §1¶7ṣ3Opaque formats include proprietary formats that can be read and edited only by proprietary word processors, SGML or XML for which the DTD and/or processing tools are not generally available, and the machine-generated HTML, PostScript or PDF produced by some word processors for output purposes only.

§1¶8§1¶8ṣ1The Title Page means, for a printed book, the title page itself, plus such following pages as are needed to hold, legibly, the material this License requires to appear in the title page. §1¶8ṣ2For works in formats which do not have any title page as such, Title Page means the text near the most prominent appearance of the work's title, preceding the beginning of the body of the text.

§1¶9§1¶9ṣ1The publisher means any person or entity that distributes copies of the Document to the public.

§1¶10§1¶10ṣ1A section Entitled XYZ means a named subunit of the Document whose title either is precisely XYZ or contains XYZ in parentheses following text that translates XYZ in another language. §1¶10ṣ2(Here XYZ stands for a specific section name mentioned below, such as Acknowledgements, Dedications, Endorsements, or History.) §1¶10ṣ3To Preserve the Title of such a section when you modify the Document means that it remains a section Entitled XYZ according to this definition.

§1¶11§1¶11ṣ1The Document may include Warranty Disclaimers next to the notice which states that this License applies to the Document. §1¶11ṣ2These Warranty Disclaimers are considered to be included by reference in this License, but only as regards disclaiming warranties: ṣ2.1any other implication that these Warranty Disclaimers may have is void and has no effect on the meaning of this License.


§2¶1§2¶1ṣ1You may copy and distribute the Document in any medium, either commercially or noncommercially, provided that this License, the copyright notices, and the license notice saying this License applies to the Document are reproduced in all copies, and that you add no other conditions whatsoever to those of this License. §2¶1ṣ2You may not use technical measures to obstruct or control the reading or further copying of the copies you make or distribute. §2¶1ṣ3However, you may accept compensation in exchange for copies. §2¶1ṣ4If you distribute a large enough number of copies you must also follow the conditions in section 3.

§2¶2§2¶2ṣ1You may also lend copies, under the same conditions stated above, and you may publicly display copies.


§3¶1§3¶1ṣ1If you publish printed copies (or copies in media that commonly have printed covers) of the Document, numbering more than 100, and the Document's license notice requires Cover Texts, you must enclose the copies in covers that carry, clearly and legibly, all these Cover Texts: ṣ1.1Front-Cover Texts on the front cover, and Back-Cover Texts on the back cover. §3¶1ṣ2Both covers must also clearly and legibly identify you as the publisher of these copies. §3¶1ṣ3The front cover must present the full title with all words of the title equally prominent and visible. §3¶1ṣ4You may add other material on the covers in addition. §3¶1ṣ5Copying with changes limited to the covers, as long as they preserve the title of the Document and satisfy these conditions, can be treated as verbatim copying in other respects.

§3¶2§3¶2ṣ1If the required texts for either cover are too voluminous to fit legibly, you should put the first ones listed (as many as fit reasonably) on the actual cover, and continue the rest onto adjacent pages.

§3¶3§3¶3ṣ1If you publish or distribute Opaque copies of the Document numbering more than 100, you must either include a machine-readable Transparent copy along with each Opaque copy, or state in or with each Opaque copy a computer-network location from which the general network-using public has access to download using public-standard network protocols a complete Transparent copy of the Document, free of added material. §3¶3ṣ2If you use the latter option, you must take reasonably prudent steps, when you begin distribution of Opaque copies in quantity, to ensure that this Transparent copy will remain thus accessible at the stated location until at least one year after the last time you distribute an Opaque copy (directly or through your agents or retailers) of that edition to the public.

§3¶4§3¶4ṣ1It is requested, but not required, that you contact the authors of the Document well before redistributing any large number of copies, to give them a chance to provide you with an updated version of the Document.


§4¶1§4¶1ṣ1You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above, provided that you release the Modified Version under precisely this License, with the Modified Version filling the role of the Document, thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it. §4¶1ṣ2In addition, you must do these things in the Modified Version:

  1. A. §4¶1.A§4¶1.Aṣ1Use in the Title Page (and on the covers, if any) a title distinct from that of the Document, and from those of previous versions (which should, if there were any, be listed in the History section of the Document). §4¶1.Aṣ2You may use the same title as a previous version if the original publisher of that version gives permission.
  2. B. §4¶1.B§4¶1.Bṣ1List on the Title Page, as authors, one or more persons or entities responsible for authorship of the modifications in the Modified Version, together with at least five of the principal authors of the Document (all of its principal authors, if it has fewer than five), unless they release you from this requirement.
  3. C. §4¶1.C§4¶1.Cṣ1State on the Title Page page in source the name of the publisher of the Modified Version, as the publisher.
  4. D. §4¶1.D§4¶1.Dṣ1Preserve all the copyright notices of the Document.
  5. E. §4¶1.E§4¶1.Eṣ1Add an appropriate copyright notice for your modifications adjacent to the other copyright notices.
  6. F. §4¶1.F§4¶1.Fṣ1Include, immediately after the copyright notices, a license notice giving the public permission to use the Modified Version under the terms of this License, in the form shown in the Addendum below.
  7. G. §4¶1.G§4¶1.Gṣ1Preserve in that license notice the full lists of Invariant Sections and required Cover Texts given in the Document's license notice.
  8. H. §4¶1.H§4¶1.Hṣ1Include an unaltered copy of this License.
  9. I. §4¶1.I§4¶1.Iṣ1Preserve the section Entitled History, Preserve its Title, and add to it an item stating at least the title, year, new authors, and publisher of the Modified Version as given on the Title Page. §4¶1.Iṣ2If there is no section Entitled History in the Document, create one stating the title, year, authors, and publisher of the Document as given on its Title Page, then add an item describing the Modified Version as stated in the previous sentence.
  10. J. §4¶1.J§4¶1.Jṣ1Preserve the network location, if any, given in the Document for public access to a Transparent copy of the Document, and likewise the network locations given in the Document for previous versions it was based on. §4¶1.Jṣ2These may be placed in the History section. §4¶1.Jṣ3You may omit a network location for a work that was published at least four years before the Document itself, or if the original publisher of the version it refers to gives permission.
  11. K. §4¶1.K§4¶1.Kṣ1For any section Entitled Acknowledgements or Dedications, Preserve the Title of the section, and preserve in the section all the substance and tone of each of the contributor acknowledgements and/or dedications given therein.
  12. L. §4¶1.L§4¶1.Lṣ1Preserve all the Invariant Sections of the Document, unaltered in their text and in their titles. §4¶1.Lṣ2Section numbers or the equivalent are not considered part of the section titles.
  13. M. §4¶1.M§4¶1.Mṣ1Delete any section Entitled Endorsements. §4¶1.Mṣ2Such a section may not be included in the Modified Version.
  14. N. §4¶1.N§4¶1.Nṣ1Do not retitle any existing section to be Entitled Endorsements or to conflict in title with any Invariant Section.
  15. O. §4¶1.O§4¶1.Oṣ1Preserve any Warranty Disclaimers.

§4¶2§4¶2ṣ1If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. §4¶2ṣ2To do this, add their titles to the list of Invariant Sections in the Modified Version's license notice. §4¶2ṣ3These titles must be distinct from any other section titles.

§4¶3§4¶3ṣ1You may add a section Entitled Endorsements, provided it contains nothing but endorsements of your Modified Version by various partiesfor example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.

§4¶4§4¶4ṣ1You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. §4¶4ṣ2Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. §4¶4ṣ3If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; ṣ3.1but you may replace the old one, on explicit permission from the previous publisher that added the old one.

§4¶5§4¶5ṣ1The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.


§5¶1§5¶1ṣ1You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.

§5¶2§5¶2ṣ1The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. §5¶2ṣ2If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. §5¶2ṣ3Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.

§5¶3§5¶3ṣ1In the combination, you must combine any sections Entitled History in the various original documents, forming one section Entitled History; ṣ1.1likewise combine any sections Entitled Acknowledgements, and any sections Entitled Dedications. §5¶3ṣ2You must delete all sections Entitled Endorsements.


§6¶1§6¶1ṣ1You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.

§6¶2§6¶2ṣ1You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.


§7¶1§7¶1ṣ1A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an aggregate if the copyright resulting from the compilation is not used to limit the legal rights of the compilation's users beyond what the individual works permit. §7¶1ṣ2When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.

§7¶2§7¶2ṣ1If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document's Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. §7¶2ṣ2Otherwise they must appear on printed covers that bracket the whole aggregate.


§8¶1§8¶1ṣ1Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. §8¶1ṣ2Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. §8¶1ṣ3You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. §8¶1ṣ4In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.

§8¶2§8¶2ṣ1If a section in the Document is Entitled Acknowledgements, Dedications, or History, the requirement (section 4) (I and K) to Preserve its Title (section 1) will typically require changing the actual title.


§9¶1§9¶1ṣ1You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. §9¶1ṣ2Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.

§9¶2§9¶2ṣ1However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated

  1. (a) ṣ1.aprovisionally, unless and until the copyright holder explicitly and finally terminates your license, and
  2. (b) ṣ1.bpermanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.

§9¶3§9¶3ṣ1Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.

§9¶4§9¶4ṣ1Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. §9¶4ṣ2If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.


§10¶1§10¶1ṣ1The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. §10¶1ṣ2Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. §10¶1ṣ3See

§10¶2§10¶2ṣ1Each version of the License is given a distinguishing version number. §10¶2ṣ2If the Document specifies that a particular numbered version of this License or any later version applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. §10¶2ṣ3If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. §10¶2ṣ4If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy's public statement of acceptance of a version permanently authorizes you to choose that version for the Document.


§11¶1§11¶1ṣ1Massive Multiauthor Collaboration Site (or MMC Site) means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. §11¶1ṣ2A public wiki that anybody can edit is an example of such a server. §11¶1ṣ3A Massive Multiauthor Collaboration (or MMC) contained in the site means any set of copyrightable works thus published on the MMC site.

§11¶2§11¶2ṣ1CC-BY-SA means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.

§11¶3§11¶3ṣ1Incorporate means to publish or republish a Document, in whole or in part, as part of another Document.

§11¶4§11¶4ṣ1An MMC is eligible for relicensing if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC,

  1. (1) ṣ1.1had no cover texts or invariant sections, and
  2. (2) ṣ1.2were thus incorporated prior to November 1, 2008.

§11¶5§11¶5ṣ1The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.

§12ADDENDUM: How to use this License for your documents

§12¶1§12¶1ṣ1To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:

§12¶2§12¶2ṣ1Copyright (C) YEAR YOUR NAME.
§12¶2ṣ2Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; ṣ2.1with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. §12¶2ṣ3A copy of the license is included in the section entitled "GNU Free Documentation License".

§12¶3§12¶3ṣ1If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the withTexts. line with this:

§12¶4§12¶4ṣ1with the Invariant Sections being LIST THEIR TITLES, with the Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.

§12¶5§12¶5ṣ1If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.

§12¶6§12¶6ṣ1If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.

flip bgunflip 

Show terms/headings