MediaWiki

Description:

MediaWiki is a wiki package originally written for Wikipedia, that is now used by several other projects of the Wikimedia Foundation and by many other wikis around the World.
MediaWiki is extremely powerful and also scaleable. It's designed to be run on a large server farm for websites that gets heavy traffic.

Pages generated by MediaWiki use their own wikitext format, simple enough that even users without any knowledge of XHTML or CSS can edit them easily.

Features:

• Permissions system
• Different skins to present the site
• User styles through custom CSS
• Printable versions of articles
• Generate a table of contents for long articles
• XHTML-compatible output
• File upload of graphics or sound files
• Automatic resizing of images
• Watch list to track changes on the articles
• Editing syntax
• Support for sub-pages
• Multiple Categories assigned to any page
• Section editing
• Anti-spam Features
• Talk pages
• Message notification
• Translated into many languages
• Inter-language link
• UTF-8 support
• RSS syndication
• RDF metadata
• Full text search
• Query API
• etc.

MediaWiki's Screenshots:

Links:

• Official WebSite:
  http://www.mediawiki.org/
  
• MediaWiki's Official Forum
  http://www.mediawiki.org/wiki/Project:Support_desk
  
• Addons:
  http://www.mediawiki.org/wiki/Category:Extensions
  
• Reviews:
  http://www.newsforge.com/article