Wikipedia

Wikipedia is a peer-directed project to create a group of encyclopedias in every major language. The project was started by Jimmy Wales and Larry Sanger in January 2001 as an accidental spin-off of Nupedia.

Wikipedia allows anyone to edit, unless they have been banned from the project. While contributors are encouraged to create accounts at Wikipedia, people may edit anonymously. All contributions of text are licensed under the Gnu Free Documentation License (GFDL). All edits are tracked and the editing history for every Wikipedia page is available, exceeding the documentation requirements of the GFDL. Anonymous contributors are identified by the IP address from which they contributed.

Wikipedia grew exponentially in its first 4 to 5 years, though article growth slowed after the one millionth article. The English Wikipedia is the world's largest wiki.

The project wrote its own wiki software called MediaWiki and released this software under the GPL, so anyone may copy it and modify it freely.

While the English Wikipedia boasts well over one million articles, many articles are on relatively trivial subjects including individual schools, very small towns, sports figures, celebrities and popular culture. For example, each of the 493 Pokemon characters has an individual article. Wikipedia judges certain articles to be important enough and well-written enough to be considered featured articles, as of 9 May 2007, there are 1391 "Featured Articles" out of 1,776,624 articles on the English Wikipedia.