GNU Free Documentation License
Encyclopedia
The GNU Free Documentation License (GNU FDL or simply GFDL) is a copyleft
license
for free documentation, designed by the Free Software Foundation
(FSF) for the GNU Project
. It is similar to the GNU General Public License
, giving readers the rights to copy, redistribute, and modify a work and requires all copies and derivatives to be available under the same license. Copies may also be sold commercially, but, if produced in larger quantities (greater than 100), the original document or source code must be made available to the work's recipient.
The GFDL was designed for manual
s, textbooks, other reference and instructional materials, and documentation which often accompanies GNU software. However, it can be used for any text-based work, regardless of subject matter. For example, the free online encyclopedia Wikipedia
used to use the GFDL for all of its text.
The first discussion draft of the GNU Free Documentation License version 2 was released on September 26, 2006, along with a draft of the new GNU Simpler Free Documentation License
.
On December 1, 2007, Jimmy Wales
announced that a long period of discussion and negotiation between and amongst the Free Software Foundation, Creative Commons, the Wikimedia Foundation
and others had produced a proposal supported by both the FSF and Creative Commons to modify the Free Documentation License in such a fashion as to allow the possibility for the Wikimedia Foundation to migrate the projects to the similar Creative Commons Attribution Share-Alike (CC-BY-SA) license. These changes were implemented on version 1.3 of the license, which includes a new provision allowing certain materials released under the license to be used under a Creative Commons Attribution Share-Alike license also.
, some of the secondary sections have various restrictions designed primarily to deal with proper attribution to previous authors.
Specifically, the authors of prior versions have to be acknowledged and certain "invariant sections" specified by the original author and dealing with his or her relationship to the subject matter may not be changed. If the material is modified, its title has to be changed (unless the prior authors give permission to retain the title).
The license also has provisions for the handling of front-cover and back-cover texts of books, as well as for "History", "Acknowledgements", "Dedications" and "Endorsements" sections. These features were added in part to make the license more financially attractive to commercial publishers of software documentation, some of whom were consulted during the drafting of the GFDL. "Endorsements" sections are intended to be used in official standard documents, where distribution of modified versions should only be permitted if they are not labeled as that standard any more.
under United States copyright law (or fair dealing
in some other countries) and does not need to be licensed to fall within the GFDL if such fair use is covered by all potential subsequent uses. One example of such liberal and commercial fair use is parody
.
Attribution-ShareAlike
license. However, version 1.3 added a new section allowing specific types of websites using the GFDL to additionally offer their work under the CC-BY-SA license.
These exemptions allow a GFDL-based collaborative project with multiple authors to transition to the CC-BY-SA 3.0 license (which would normally require the permission of every author), if the work satisfies several conditions:
To prevent the clause from being used as a general compatibility measure, the license itself only allowed the change to occur before August 1, 2009. At the release of version 1.3, the FSF stated that all content added before November 1, 2008 to Wikipedia as an example satisfied the conditions. The Wikimedia Foundation itself after a public referendum, invoked this process to dual-license content released under the GFDL under the CC-BY-SA license in June 2009, and adopted a foundation-wide attribution policy for the use of content from Wikimedia Foundation projects.
, has been successfully enforced in such a setting. Although the content of Wikipedia
has been plagiarized and used in violation of the GFDL by other sites, such as Baidu Baike
, no contributors have ever tried to bring an organization to court due to violation of the GFDL. In the case of Baidu, Wikipedia representatives asked the site and its contributors to respect the terms of the licenses and to make proper attributions.
(DRM) systems applies to valid usages, like for "private copies made and not distributed".
Notably, the Debian
project and Nathanael Nerode have raised objections. In 2006, Debian developers voted to consider works licensed under the GFDL to comply with their Debian Free Software Guidelines
provided the invariant section clauses are not used. However, their resolution stated that even without invariant sections, GFDL-licensed software documentation "is still not free of trouble", namely because of its incompatibility with the major free software licenses.
Critics recommend the use of alternative licenses such as the BSD Documentation License or the GNU GPL.
The FLOSS Manuals
foundation, an organization devoted to creating manuals for free software, decided to eschew the GFDL in favor of the GPL for its texts in 2007, citing the incompatibility between the two, difficulties in implementing the GFDL, and the fact that the GFDL "does not allow for easy duplication and modification", especially for digital documentation.
A criticism of this language is that it is too broad, because it applies to private copies made but not distributed. This means that a licensee is not allowed to save document copies "made" in a proprietary file format or using encryption.
In 2003, Richard Stallman
said about the above sentence on the debian-legal mailing list:
At any rate, it is likely that laws against computer trespass and malicious hacking
will protect private copies even if usage of file controls is indeed forbidden.
after copyright
expires.
Richard Stallman
said about invariant sections on the debian-legal mailing list:
in both directions with the GPL: Material under the GNU FDL cannot be put into GPL code and GPL code cannot be put into a GNU FDL manual. At the June 22nd and 23rd 2006 international GPLv3 conference in Barcelona, Eben Moglen
hinted that a future version of the GPL could be made suitable for documentation:
, a web site dedicated to free content
travel guides, chose not to use the GFDL because it considers it unsuitable for short printed texts.
editor is rapidly maturing, but has not yet reached version 1.0. This section, which was rewritten somewhat between versions 1.1 and 1.2 of the license, uses the terms "widely available" and "proprietary" inconsistently and without defining them. According to a strict interpretation of the license, the references to "generic text editors" could be interpreted as ruling out any non-human-readable format even if used by an open-source word-processor; according to a loose interpretation, however, Microsoft Word .doc format could qualify as transparent, since a subset of .doc files can be edited perfectly using OpenOffice.org
, and the format therefore is not one "that can be read and edited only by proprietary word processors."
Copyleft
Copyleft is a play on the word copyright to describe the practice of using copyright law to offer the right to distribute copies and modified versions of a work and requiring that the same rights be preserved in modified versions of the work...
license
License
The verb license or grant licence means to give permission. The noun license or licence refers to that permission as well as to the document recording that permission.A license may be granted by a party to another party as an element of an agreement...
for free documentation, designed by the Free Software Foundation
Free Software Foundation
The Free Software Foundation is a non-profit corporation founded by Richard Stallman on 4 October 1985 to support the free software movement, a copyleft-based movement which aims to promote the universal freedom to create, distribute and modify computer software...
(FSF) for the GNU Project
GNU Project
The GNU Project is a free software, mass collaboration project, announced on September 27, 1983, by Richard Stallman at MIT. It initiated GNU operating system development in January, 1984...
. It is similar to the GNU General Public License
GNU General Public License
The GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....
, giving readers the rights to copy, redistribute, and modify a work and requires all copies and derivatives to be available under the same license. Copies may also be sold commercially, but, if produced in larger quantities (greater than 100), the original document or source code must be made available to the work's recipient.
The GFDL was designed for manual
User guide
A user guide or user's guide, also commonly known as a manual, is a technical communication document intended to give assistance to people using a particular system...
s, textbooks, other reference and instructional materials, and documentation which often accompanies GNU software. However, it can be used for any text-based work, regardless of subject matter. For example, the free online encyclopedia Wikipedia
Wikipedia
Wikipedia is a free, web-based, collaborative, multilingual encyclopedia project supported by the non-profit Wikimedia Foundation. Its 20 million articles have been written collaboratively by volunteers around the world. Almost all of its articles can be edited by anyone with access to the site,...
used to use the GFDL for all of its text.
Timeline
The GFDL was released in draft form for feedback in September 1999. After revisions, version 1.1 was issued in March 2000, version 1.2 in November 2002, and version 1.3 in November 2008. The current state of the license is version 1.3.The first discussion draft of the GNU Free Documentation License version 2 was released on September 26, 2006, along with a draft of the new GNU Simpler Free Documentation License
GNU Simpler Free Documentation License
The GNU Simpler Free Documentation License is a proposed version of the GNU Free Documentation License that has no requirements to maintain Cover Texts and Invariant Sections...
.
On December 1, 2007, Jimmy Wales
Jimmy Wales
Jimmy Donal "Jimbo" Wales is an American Internet entrepreneur best known as a co-founder and promoter of the online non-profit encyclopedia Wikipedia and the Wikia company....
announced that a long period of discussion and negotiation between and amongst the Free Software Foundation, Creative Commons, the Wikimedia Foundation
Wikimedia Foundation
Wikimedia Foundation, Inc. is an American non-profit charitable organization headquartered in San Francisco, California, United States, and organized under the laws of the state of Florida, where it was initially based...
and others had produced a proposal supported by both the FSF and Creative Commons to modify the Free Documentation License in such a fashion as to allow the possibility for the Wikimedia Foundation to migrate the projects to the similar Creative Commons Attribution Share-Alike (CC-BY-SA) license. These changes were implemented on version 1.3 of the license, which includes a new provision allowing certain materials released under the license to be used under a Creative Commons Attribution Share-Alike license also.
Conditions
Material licensed under the current version of the license can be used for any purpose, as long as the use meets certain conditions.- All previous authors of the work must be attributedAttribution (copyright)Attribution in copyright law, is the requirement to acknowledge or credit the author of a work which is used or appears in another work. Attribution is required by most copyright and copyleft licenses, such as the GNU Free Documentation License and Creative Commons licenses.Attribution is often...
. - All changes to the work must be logged.
- All derivative workDerivative workIn United States copyright law, a derivative work is an expressive creation that includes major, copyright-protected elements of an original, previously created first work .-Definition:...
s must be licensed under the same license. - The full text of the license, unmodified invariant sections as defined by the author if any, and any other added warranty disclaimers (such as a general disclaimer alerting readers that the document may not be accurate for example) and copyright notices from previous versions must be maintained.
- Technical measures such as DRMDigital rights managementDigital rights management is a class of access control technologies that are used by hardware manufacturers, publishers, copyright holders and individuals with the intent to limit the use of digital content and devices after sale. DRM is any technology that inhibits uses of digital content that...
may not be used to control or obstruct distribution or editing of the document.
Secondary sections
The license explicitly separates any kind of "Document" from "Secondary Sections", which may not be integrated with the Document, but exist as front-matter materials or appendices. Secondary sections can contain information regarding the author's or publisher's relationship to the subject matter, but not any subject matter itself. While the Document itself is wholly editable, and is essentially covered by a license equivalent to (but mutually incompatible with) the GNU General Public LicenseGNU General Public License
The GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....
, some of the secondary sections have various restrictions designed primarily to deal with proper attribution to previous authors.
Specifically, the authors of prior versions have to be acknowledged and certain "invariant sections" specified by the original author and dealing with his or her relationship to the subject matter may not be changed. If the material is modified, its title has to be changed (unless the prior authors give permission to retain the title).
The license also has provisions for the handling of front-cover and back-cover texts of books, as well as for "History", "Acknowledgements", "Dedications" and "Endorsements" sections. These features were added in part to make the license more financially attractive to commercial publishers of software documentation, some of whom were consulted during the drafting of the GFDL. "Endorsements" sections are intended to be used in official standard documents, where distribution of modified versions should only be permitted if they are not labeled as that standard any more.
Commercial redistribution
The GFDL requires the ability to "copy and distribute the Document in any medium, either commercially or noncommercially" and therefore is incompatible with material that excludes commercial re-use. As mentioned above, the GFDL was designed with commercial publishers in mind, as Stallman explained: Material that restricts commercial re-use is incompatible with the license and cannot be incorporated into the work. However, incorporating such restricted material may be fair useFair use
Fair use is a limitation and exception to the exclusive right granted by copyright law to the author of a creative work. In United States copyright law, fair use is a doctrine that permits limited use of copyrighted material without acquiring permission from the rights holders...
under United States copyright law (or fair dealing
Fair dealing
Fair dealing is a limitation and exception to the exclusive right granted by copyright law to the author of a creative work, which is found in many of the common law jurisdictions of the Commonwealth of Nations....
in some other countries) and does not need to be licensed to fall within the GFDL if such fair use is covered by all potential subsequent uses. One example of such liberal and commercial fair use is parody
Parody
A parody , in current usage, is an imitative work created to mock, comment on, or trivialise an original work, its subject, author, style, or some other target, by means of humorous, satiric or ironic imitation...
.
Compatibility with Creative Commons licensing terms
Although the two licenses work on similar copyleft principles, the GFDL is not compatible with the Creative CommonsCreative Commons
Creative Commons is a non-profit organization headquartered in Mountain View, California, United States devoted to expanding the range of creative works available for others to build upon legally and to share. The organization has released several copyright-licenses known as Creative Commons...
Attribution-ShareAlike
Creative Commons licenses
Creative Commons licenses are several copyright licenses that allow the distribution of copyrighted works. The licenses differ by several combinations that condition the terms of distribution. They were initially released on December 16, 2002 by Creative Commons, a U.S...
license. However, version 1.3 added a new section allowing specific types of websites using the GFDL to additionally offer their work under the CC-BY-SA license.
These exemptions allow a GFDL-based collaborative project with multiple authors to transition to the CC-BY-SA 3.0 license (which would normally require the permission of every author), if the work satisfies several conditions:
- The work must have been produced on a "Massive Multiauthor Collaboration Site" (MMC), such as a public wikiWikiA wiki is a website that allows the creation and editing of any number of interlinked web pages via a web browser using a simplified markup language or a WYSIWYG text editor. Wikis are typically powered by wiki software and are often used collaboratively by multiple users. Examples include...
for example. - If external content originally published on a MMC is present on the site, the work must have been licensed under Version 1.3 of the GNU FDL, or an earlier version but with the "or any later version" declaration, with no cover texts or invariant sections. If it was not originally published on an MMC, it can only be relicensed if it were added to an MMC before November 1, 2008.
To prevent the clause from being used as a general compatibility measure, the license itself only allowed the change to occur before August 1, 2009. At the release of version 1.3, the FSF stated that all content added before November 1, 2008 to Wikipedia as an example satisfied the conditions. The Wikimedia Foundation itself after a public referendum, invoked this process to dual-license content released under the GFDL under the CC-BY-SA license in June 2009, and adopted a foundation-wide attribution policy for the use of content from Wikimedia Foundation projects.
Enforcement
There have currently been no cases involving the GFDL in a court of law, although its sister license for software, the GNU General Public LicenseGNU General Public License
The GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....
, has been successfully enforced in such a setting. Although the content of Wikipedia
Wikipedia
Wikipedia is a free, web-based, collaborative, multilingual encyclopedia project supported by the non-profit Wikimedia Foundation. Its 20 million articles have been written collaboratively by volunteers around the world. Almost all of its articles can be edited by anyone with access to the site,...
has been plagiarized and used in violation of the GFDL by other sites, such as Baidu Baike
Baidu Baike
Baidu Encyclopedia is a Chinese language collaborative Web-based encyclopedia provided by the Chinese search engine Baidu. Like Baidu itself, the encyclopedia is heavily self-censored in line with government regulations....
, no contributors have ever tried to bring an organization to court due to violation of the GFDL. In the case of Baidu, Wikipedia representatives asked the site and its contributors to respect the terms of the licenses and to make proper attributions.
Criticism
Critics consider the GFDL a non-free license. Some reasons for this are that the GFDL allows "invariant" text which cannot be modified or removed, and that its prohibition against digital rights managementDigital rights management
Digital rights management is a class of access control technologies that are used by hardware manufacturers, publishers, copyright holders and individuals with the intent to limit the use of digital content and devices after sale. DRM is any technology that inhibits uses of digital content that...
(DRM) systems applies to valid usages, like for "private copies made and not distributed".
Notably, the Debian
Debian
Debian is a computer operating system composed of software packages released as free and open source software primarily under the GNU General Public License along with other free software licenses. Debian GNU/Linux, which includes the GNU OS tools and Linux kernel, is a popular and influential...
project and Nathanael Nerode have raised objections. In 2006, Debian developers voted to consider works licensed under the GFDL to comply with their Debian Free Software Guidelines
Debian Free Software Guidelines
The Debian Free Software Guidelines is a set of guidelines that the Debian Project uses to determine whether a software license is a free software license, which in turn is used to determine whether a piece of software can be included in Debian...
provided the invariant section clauses are not used. However, their resolution stated that even without invariant sections, GFDL-licensed software documentation "is still not free of trouble", namely because of its incompatibility with the major free software licenses.
Critics recommend the use of alternative licenses such as the BSD Documentation License or the GNU GPL.
The FLOSS Manuals
Floss manuals
The FLOSS Manuals is a non-profit foundation founded in 2006 and based in the Netherlands. The foundation is focused on the creation of quality documentation about how to use free software....
foundation, an organization devoted to creating manuals for free software, decided to eschew the GFDL in favor of the GPL for its texts in 2007, citing the incompatibility between the two, difficulties in implementing the GFDL, and the fact that the GFDL "does not allow for easy duplication and modification", especially for digital documentation.
DRM clause
The GNU FDL contains the statement:A criticism of this language is that it is too broad, because it applies to private copies made but not distributed. This means that a licensee is not allowed to save document copies "made" in a proprietary file format or using encryption.
In 2003, Richard Stallman
Richard Stallman
Richard Matthew Stallman , often shortened to rms,"'Richard Stallman' is just my mundane name; you can call me 'rms'"|last= Stallman|first= Richard|date= N.D.|work=Richard Stallman's homepage...
said about the above sentence on the debian-legal mailing list:
At any rate, it is likely that laws against computer trespass and malicious hacking
Hacker (computer security)
In computer security and everyday language, a hacker is someone who breaks into computers and computer networks. Hackers may be motivated by a multitude of reasons, including profit, protest, or because of the challenge...
will protect private copies even if usage of file controls is indeed forbidden.
Invariant sections
A GNU FDL work can quickly be encumbered because a new, different title must be given and a list of previous titles must be kept. This could lead to the situation where there are a whole series of title pages, and dedications, in each and every copy of the book if it has a long lineage. These pages cannot be removed until the work enters the public domainPublic domain
Works are in the public domain if the intellectual property rights have expired, if the intellectual property rights are forfeited, or if they are not covered by intellectual property rights at all...
after copyright
Copyright
Copyright is a legal concept, enacted by most governments, giving the creator of an original work exclusive rights to it, usually for a limited time...
expires.
Richard Stallman
Richard Stallman
Richard Matthew Stallman , often shortened to rms,"'Richard Stallman' is just my mundane name; you can call me 'rms'"|last= Stallman|first= Richard|date= N.D.|work=Richard Stallman's homepage...
said about invariant sections on the debian-legal mailing list:
GPL incompatible in both directions
The GNU FDL is incompatibleLicense compatibility
License compatibility refers to the problem with licenses applied to works subject to copyright, particularly licenses of software packages, which can contain contradictory requirements, rendering it impossible to combine source code from such packages or content from such works in order to create...
in both directions with the GPL: Material under the GNU FDL cannot be put into GPL code and GPL code cannot be put into a GNU FDL manual. At the June 22nd and 23rd 2006 international GPLv3 conference in Barcelona, Eben Moglen
Eben Moglen
Eben Moglen is a professor of law and legal history at Columbia University, and is the founder, Director-Counsel and Chairman of Software Freedom Law Center, whose client list includes numerous pro bono clients, such as the Free Software Foundation....
hinted that a future version of the GPL could be made suitable for documentation:
Burdens when printing
The GNU FDL requires that licensees, when printing a document covered by the license, must also include "this License, the copyright notices, and the license notice saying this License applies to the Document". This means that if a licensee prints out a copy of an article whose text is covered under the GNU FDL, he or she must also include a copyright notice and a physical printout of the GNU FDL, which is a significantly large document in itself. Worse, the same is required for the standalone use of just one (for example, Wikipedia) image. WikitravelWikitravel
-External links:* *...
, a web site dedicated to free content
Free content
Free content, or free information, is any kind of functional work, artwork, or other creative content that meets the definition of a free cultural work...
travel guides, chose not to use the GFDL because it considers it unsuitable for short printed texts.
Transparent formats
The definition of a "transparent" format is complicated, and may be difficult to apply. For example, drawings are required to be in a format that allows them to be revised straightforwardly with "some widely available drawing editor." The definition of "widely available" may be difficult to interpret, and may change over time, since, e.g., the open-source InkscapeInkscape
Inkscape is a free software vector graphics editor, licensed under the GNU General Public License. Its goal is to implement full support for the Scalable Vector Graphics 1.1 standard....
editor is rapidly maturing, but has not yet reached version 1.0. This section, which was rewritten somewhat between versions 1.1 and 1.2 of the license, uses the terms "widely available" and "proprietary" inconsistently and without defining them. According to a strict interpretation of the license, the references to "generic text editors" could be interpreted as ruling out any non-human-readable format even if used by an open-source word-processor; according to a loose interpretation, however, Microsoft Word .doc format could qualify as transparent, since a subset of .doc files can be edited perfectly using OpenOffice.org
OpenOffice.org
OpenOffice.org, commonly known as OOo or OpenOffice, is an open-source application suite whose main components are for word processing, spreadsheets, presentations, graphics, and databases. OpenOffice is available for a number of different computer operating systems, is distributed as free software...
, and the format therefore is not one "that can be read and edited only by proprietary word processors."
Other free content licenses
Some of these were developed independently of the GNU FDL, while others were developed in response to perceived flaws in the GNU FDL.- Creative Commons licensesCreative Commons licensesCreative Commons licenses are several copyright licenses that allow the distribution of copyrighted works. The licenses differ by several combinations that condition the terms of distribution. They were initially released on December 16, 2002 by Creative Commons, a U.S...
- Design Science LicenseDesign Science LicenseDesign Science License is a copyleft license for free content such as text, images, music and other content but not for documentation or source code. The DSL was written by Michael Stutz.-External links:*...
- Free Art licenseFree Art licenseThe Free Art License is a copyleft license that grants the right to freely copy, distribute, and transform creative works without needing the author's explicit permission.The Free Art License recognizes and protects these rights...
- FreeBSD Documentation LicenseFreeBSD Documentation LicenseThe FreeBSD Documentation License is the license that covers most of the documentation for the FreeBSD operating system.The license is very similar to the 2-clause Simplified BSD License used by the rest of FreeBSD, however, it makes the meanings of "source code" and "compile" less ambiguous in the...
- Open Content LicenseOpen Content LicenseThe Open Content License is a copyleft license designed for distribution of open content material. This license is not compatible with the any other license in that it requires derivative works to be licensed under the Open Content License....
- Open Gaming LicenseOpen Gaming LicenseThe Open Game License may be used by game developers to grant permission to modify, copy, and redistribute some of the content designed for their games, notably game mechanics.-Language of the licence:The OGL describes two forms of content:...
- Open Publication LicenseOpen Publication LicenseOpen Publication License is a license open publications created by the Open Content Project, which now recommends using one of the Creative Commons licenses....
- WTFPLWTFPLThe WTFPL is an infrequently used, extremely permissive free software license. The original Version 1.0 license, released March 2000, was written by Banlu Kemiyatorn who used it for Window Maker artwork. Samuel “Sam” Hocevar, a French programmer who was the Debian project leader from 17 April...
List of projects that use the GFDL
- Most projects of the Wikimedia FoundationWikimedia FoundationWikimedia Foundation, Inc. is an American non-profit charitable organization headquartered in San Francisco, California, United States, and organized under the laws of the state of Florida, where it was initially based...
, including WikipediaWikipediaWikipedia is a free, web-based, collaborative, multilingual encyclopedia project supported by the non-profit Wikimedia Foundation. Its 20 million articles have been written collaboratively by volunteers around the world. Almost all of its articles can be edited by anyone with access to the site,...
(excluding WikinewsWikinewsWikinews is a free-content news source wiki and a project of the Wikimedia Foundation. The site works through collaborative journalism. Wikipedia co-founder Jimmy Wales has distinguished Wikinews from Wikipedia by saying "on Wikinews, each story is to be written as a news story as opposed to an...
) - On June 15, 2009, the Section 11 clauses were used to dual-license the content of these wikis under the Creative Commons Attribution Share-Alike license and GFDL. - An Anarchist FAQAn Anarchist FAQ"An Anarchist FAQ" is an FAQ written by an international work group of social anarchists connected through the internet. It documents anarchist theory and ideas while arguing that social anarchism is a better form of anarchism than individualist anarchism, which it critiques. It also explores other...
- CitizendiumCitizendiumCitizendium is an English-language wiki-based free encyclopedia project launched by Larry Sanger, who co-founded Wikipedia in 2001....
- the project uses GFDL for articles originally from Wikipedia. - Free On-line Dictionary of ComputingFree On-line Dictionary of ComputingThe Free On-line Dictionary of Computing is an online, searchable, encyclopedic dictionary of computing subjects. It was founded in 1985 by Denis Howe and is hosted by Imperial College London...
- Last.fmLast.fmLast.fm is a music website, founded in the United Kingdom in 2002. It has claimed 30 million active users in March 2009. On 30 May 2007, CBS Interactive acquired Last.fm for UK£140m ....
- artists descriptions are under GFDL - Marxists Internet ArchiveMarxists Internet ArchiveMarxists Internet Archive is a volunteer based non-profit organization that maintains a multi-lingual Internet archive of Marxist writers and other similar authors...
- OpenHistory
- PlanetMathPlanetMathPlanetMath is a free, collaborative, online mathematics encyclopedia. The emphasis is on rigour, openness, pedagogy, real-time content, interlinked content, and also community of about 24,000 people with various maths interests. Intended to be comprehensive, the project is hosted by the Digital...
- SourceWatchSourceWatchSourceWatch is an internet wiki site that is a collaborative project of the liberal Center for Media and Democracy...
- The specification documents that define TRAKTRAKTRAK is a general enterprise architecture framework aimed at systems engineers based on MODAF 1.2.-History:TRAK was originally commissioned by London Underground Limited...
, an enterprise architecture framework, are released under the GFDL. - The Virginia Commonwealth UniversityVirginia Commonwealth UniversityVirginia Commonwealth University is a public university located in Richmond, Virginia. It comprises two campuses in the Downtown Richmond area, the product of a merger between the Richmond Professional Institute and the Medical College of Virginia in 1968...
Mathematics Department has begun commercially publishing mathematics texts licensed under the GDFL, including Abstract Algebra by Thomas W. Judson. - the Baseball-ReferenceBaseball-ReferenceBaseball-Reference.com is a website providing statistics for every player in Major League Baseball history. The site is often used by major media organizations and baseball broadcasters as a source for statistics.-History:...
's BR Bullpen, a free user-contributed baseball wiki
See also
- BSD license
- CopyleftCopyleftCopyleft is a play on the word copyright to describe the practice of using copyright law to offer the right to distribute copies and modified versions of a work and requiring that the same rights be preserved in modified versions of the work...
- CopyrightCopyrightCopyright is a legal concept, enacted by most governments, giving the creator of an original work exclusive rights to it, usually for a limited time...
- Free software license
- GNUGNUGNU is a Unix-like computer operating system developed by the GNU project, ultimately aiming to be a "complete Unix-compatible software system"...
- Non-commercial educationalNon-commercial educationalThe term non-commercial educational applies to a radio station or TV station that does not accept on air advertisements , as defined in the United States by the Federal Communications Commission . NCE stations do not pay broadcast license fees for their non-profit uses of the radio spectrum...
- Open contentOpen contentOpen content or OpenContent is a neologism coined by David Wiley in 1998 which describes a creative work that others can copy or modify. The term evokes open source, which is a related concept in software....
- Share-alikeShare-alikeShare-Alike is a descriptive term used in the Creative Commons project for copyright licenses which include certain copyleft provisions. The Share-Alike license comes in two varieties, CC-BY-SA and CC-BY-NC-SA.-Share-alike license types:...
- Software licensingSoftware licensingA software license is a legal instrument governing the usage or redistribution of software. All software is copyright protected, except material in the public domain. Contractual confidentiality is another way of protecting software...
External links
- Guide to the new drafts of documentation licenses
- GFDL official text
- Free Software and Free Manuals, essay by Richard Stallman
- Apple's Common Documentation License, an alternative license