Wikimedia Commons (also called Commons) is a freely licensed repository of digital images, sounds and other multimedia files. It is a project of the Wikimedia Foundation, which on 4 December 2012 reached the threshold of 15 million files, constituting one of the largest archives of multimedia resources for educational and documentary purposes freely usable on the web.
The files sent to this archive can be used directly by all other projects located on the Wikimedia servers, including Wikipedia, Wikibooks, Wikinews, Wikispecies, as if they were uploaded locally to each individual project (in some cases, however, it is possible that the use of certain images is prohibited in specific projects due to legislative problems due to local laws).
The project was born on 7 September 2004 with the aim of establishing a centralized repository for images and other multimedia resources of the Wikimedia projects (previously every Wikimedia project and every edition of Wikipedia required you to upload the multimedia files to its database).
On May 24, 2005 Wikimedia Commons reached the milestone of 100,000 uploaded media files. It was also the first Wikimedia project to use MediaWiki version 1.4 software. The default language for Commons is English; however, the interface can be configured in user preferences to use any other language. Many pages have already been translated into various languages.
Since 2005, Wikimedia Commons has not allowed the uploading of files with non-free licenses, including licenses that restrict commercial use of multimedia content or that are released in fair use. Among the free licenses accepted by the Commons, the GFDL and the free Creative Commons licenses (i.e. which do not restrict use to non-commercial purposes only and which do not prevent modification of the content).
Since May 2005 the site has amassed a large collection. It collects over 10,000 reproductions of public domain paintings from ancient to modern times, over 7,000 pronunciation files in various languages, hundreds of public domain recordings of classical music, and a growing collection of historical speech footage.
The purpose of Wikimedia Commons is to provide an archive of multimedia files "which makes educational multimedia content in the public domain and free of charge available to all and which acts as a common repository for the various projects of the Wikimedia Foundation". The term "educational" is to be understood in its broad sense of "provision of knowledge; instructive or informative".
Most Wikimedia projects still allow local uploads that are not visible to other projects or languages, but this option is meant to be used primarily for material (such as fair use content) allowed by local project policies, but which would not permitted under the copyright policy of Commons. Wikimedia Commons itself does not allow fair use or uploading with non-free licenses, including licenses that restrict commercial use of materials or prohibit derivative works. For this reason, Wikimedia Commons always hosts free licensed media and eliminates copyright infringement. Acceptable licenses include Creative Commons Attribution and Attribution / ShareAlike licenses, other free content, and free software and public domain licenses.
The default language for Commons is English, but registered users can customize their interface to use any other available UI translation. Many content pages, especially policy pages and portals, have been translated into various languages. Files on Wikimedia Commons are categorized using MediaWiki's category system. In addition, they are often collected on the individual pages of news galleries. Although the project was o