Wikimedia Commons is the central repository for media files intended to be used on the various Wikimedia projects. Images uploaded to the Wikimedia Commons are usable on any of the Wikimedia sites, such as Wikipedia. With rare exception, all files archived at Wikimedia Commons are either public domain or Creative Commons Licensed files that can be used at CreationWiki.
Although it is recommended that users of the Wikimedia projects upload their files to Wikimedia Commons, there is no requirement to do so. A great many usable files may be found on Wikimedia project sites, such as Wikipedia, that are not available on the central repository.
The CreationWiki has a similar central repository for our media files called the Media Pool. We also strongly recommend that CreationWiki users upload to the Media Pool when placing files on CreationWiki sites.
- From Wikimedia Commons
Wikimedia Commons is a media repository that is created and maintained not by paid-for artists, but by volunteers. Its name "Wikimedia Commons" is derived from that of the umbrella project "Wikimedia" managing all Wikimedia projects and from the plural noun "commons" as its contents are shared by different language versions and different kinds of Wikimedia projects. Thus it provides a central repository for freely licensed photographs, diagrams, animations, music, spoken text, video clips, and media of all sorts that are useful for any Wikimedia project.
Wikimedia Commons uses the same wiki-technology as Wikipedia and thus everyone can edit it easily and without advanced technical skills directly in the web browser. Unlike media files uploaded on other projects, files uploaded to Wikimedia Commons can be embedded on pages of all Wikimedia projects without the need to separately upload them there.
Launched on September 7, 2004, Wikimedia Commons hit the 100,000 uploaded media file milestone on May 24, 2005 and currently contains 1,031,473 files and 50,611 collections (numbers in English notation). More background information about the Wikimedia Commons project itself can be found in the General disclaimer, at the Wikipedia page about Wikimedia Commons and its page in Meta-wiki.
Unlike traditional media repositories Wikimedia Commons is free. Everyone is allowed to copy, use and modify any files here freely as long the source and the authors are credited and as long as users release their copies/improvements under the same freedom to others. The Wikimedia Commons database itself and the texts in it are licensed under the GNU Free Documentation License. The license conditions of each individual media file can be found on their description pages.