The Wikimedia Foundation is the non-profit organization that operates Wikipedia, the free encyclopedia. According to comScore Media Metrix, Wikipedia and the other projects operated by the Wikimedia Foundation receive more than 398 million unique visitors per month, making them the 5th most popular web property worldwide (September 2010). Available in more than 270 languages, Wikipedia contains more than 17 million articles contributed by a global volunteer community of more than 100,000 people. Based in San Francisco, California, the Wikimedia Foundation is an audited, 501(c)(3) charity that is funded primarily through donations and grants. The Wikimedia Foundation was created in 2003 to manage the operation of Wikipedia and its sister projects. It currently employs 62 staff members. Wikimedia is supported by local chapter organizations in 30 countries or regions.