WikiPedia
MediaWiki is written for Wikipedia, a Web-based multilingual encyclopedia. The Wikimedia Foundation is the parent organization of Wikipedia, Wiktionary, Wikiquote, Wikibooks (including Wikijunior and Wikiversity), Wikisource, In Memoriam 9/11, Wikimedia Commons, Wikispecies, and Wikinews. It is a non-profit corporation based in St. Petersburg, Florida (USA).
Wikipedia
The content of Wikipedia is made by volunteers. Since Wikipedia is also a wiki the content is shared, can be read, changed, written and deleted by anyone with access to a web-browser.