Jimmy Wales. Wikipedia is a free online encyclopedia that anyone can edit, and millions already have. Wikipedia's purpose is to benefit readers by presenting information on all branches of knowledge.

"Wiki" (pronounced [wiki]) is a Hawaiian word meaning "quick". The online encyclopedia project Wikipedia is the most popular wiki-based website, as well being one of the most popular websites on the entire internet, having been ranked consistently as such since at least 2007.

Wikipedia was launched on January 15, 2001 as a single English-language edition at www.wikipedia.com, and was announced by Sanger on the Nupedia mailing list. The name originated from a blend of the words wiki and encyclopedia.

The name was suggested by Sanger on 11 January 2001 as a portmanteau of the words wiki (Hawaiian for "quick") and encyclopedia. The wikipedia.com and wikipedia.org domain names were registered on 12 and 13 January, respectively, with wikipedia.org being brought online on the same day.