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The Wikimedia Foundation, Inc. (WMF) is an American 501(c)(3) nonprofit organization headquartered in San Francisco, California, and registered there as a charitable foundation. The foundation is most known for being the host of Wikipedia, one of the most visited websites in the world. It also hosts fourteen related open collaboration projects, and supports the development of MediaWiki, the wiki software which underpins them all. The foundation was established in 2003 in St. Petersburg, Florida by Jimmy Wales, as a non-profit way to fund Wikipedia and other wiki projects which had previously been hosted by Bomis, Wales' for-profit company.