MediaWiki is a free software package that is was originally written for Wikipedia. But now is used by several other projects of the Wikimedia foundation which is a non-profit organization and by many other wikis that include MediaWiki.
org. What is more, some of the content of the site might be translated into different languages, but the primary language for the site is english. The site is organized into different categories for you to choose from. The ones that are featured at the site are: browse categories, community portal, recent changes, download: mediawiki, extensions; support: user help, technical manual, faq, support desk; development: bug tracker, browse svn, download from svn, code docs; communication: irc, mailing lists; toolbox: what links here, related changes, upload file, special pages, printable link, news, current versions, developers: submitting a patch, svn commit access, reference; system administrators: installing / upgrading, configuring and third-party extensions. In addition, you can join the disscusions at the site so you can chat with other users about MediaWiki or other issues. 
