Wikipedia

Wikipedia is a free, web-based, collaborative, multilingual encyclopedia project supported by the non-profit Wikimedia Foundation. It was launched on January 15, 2001, by Jimmy Wales and Larry Sanger.

Wikipedia's name is a portmanteau of "wiki" (a type of collaborative website) and "encyclopedia." It's built on the idea that anyone can edit most of its articles, making it one of the largest and most popular general reference works on the Internet.