The Wikimedia Foundation is the non-profit organization responsible for a large number of very active wikis, as well as the MediaWiki wiki engine. The foundations' wikis include Wikipedia (encyclopedias), Wikiquote (quotations), Wikibooks (open content textbooks), Wikinews (news source), Wikisource (free content primary and secondary source texts), Wikispecies (a free species directory), and Wiktionary (dictionary). Most of these wikis have versions written in many different languages. There is also the Wikimedia Commons (for images, videos and other data files that can be used by all the Wikimedia projects), the Wikimedia Meta-Wiki (for issues common to all Wikimedia projects).

All Wikimedia Foundation projects (edit) • (category)

Wikipedia • Wiktionary • Wikiquote • Wikibooks • Wikisource • Wikispecies • Wikinews • Wikiversity • Commons • MediaWiki • Meta-Wiki • Incubator • Wikimania • Outreach • Toolserver • Statistics • Wikitech • Strategic Planning • Labs • Downloads • Usability Initiative • Wikidata