Joomla is an open source content management system. This site is built using Joomla and I would recommend it to anyone who wants to run sites based on content. I have found the Joomla logo to be very creative but never really understood what it meant until I searched for it today.
The Joomla! logo consists of the logotype and the mark. The mark represents what Joomla! is about...a community coming together as one. If you observe closely, the mark is made up of four "J's" rotated and linked together that represent the community coming together as one. This logo has been developed to promote high visibility of the mark balanced with clear legibility of the name.