is a media file repository
- making available public domain and freely-licensed educational media content (images, sound and video clips)
- common repository for the various projects of the Wikimedia Foundation
Unlike traditional media repositories, Wikimedia Commons is free. Everyone is allowed to copy, use and modify any files here freely as long as they follow the terms specified by the author; this often means crediting the source and author(s) appropriately and releasing copies/improvements under the same freedom to others.
Some select repositories:
Disciplinary Repositories listed on the Open Access Directory
OA in individual disciplines (from Informationsplattform Open Access, swtich to English, links to separate pages on 15 fields)