MediaWiki

MediaWiki is a Wiki software package licensed under the GNU General Public License. It is written in PHP and uses an underlying MySQL relational database. Its logo symbolizes how its markup language uses brackets picture of flower to link articles together, in contrast to CamelCase. Mediawiki is being developed by the Wikimedia Foundation. Lead developer is Brion Vibber. from wikipedia

Related: Wikimedia, HowTo/BecomeAMediawikiHacker

We just upgraded to Mediawiki 1.4.

New features in Mediawiki 1.4

 * 'Recentchanges Patrol' to mark new edits that haven't yet been viewed.
 * New, searchable deletion/upload/protection logs
 * Image gallery generation (Special:Newimages and