5 Well Managed Open Source CMSs you can trust.
JOOMLA!
Joomla! is a free open source content management system for publishing content on the World Wide Web and intranets. The system includes features such as page caching to improve performance, RSS feeds, printable versions of pages, news flashes, blogs, polls, website searching, and language internationalization. Joomla is licensed under the GPL, and is the result of a fork of Mambo.
Visit: http://www.joomla.org
MAMBO
Mambo (formerly named Mambo Open Source or MOS) is a free software / open source content management system (CMS) for creating and managing websites through a simple web interface. It has attracted many users due to its ease of use. Mambo also includes more advanced features such as page caching to improve performance on busy sites, advanced templating techniques, and a fairly robust API. It can also automate many tasks such as web indexing for static pages. Mambo can provide RSS feeds, printable versions of pages, news flashes, blogs, forums, polls, calendars, website searching, language internationalization, and other possibilities.
Visit: http://mambo-developer.org/
TYPO3
Initially authored by Kasper Skårhøj, it is available for free and licensed under the GNU General Public License. Today, the core of TYPO3 is developed by two teams in a maintenance tree (4.x, leader Michael Stucki) and a development tree (5.x, leader Robert Lemke). Independent authors have contributed hundreds of pluggable extensions.
TYPO3 offers full flexibility and extendability while featuring an accomplished set of ready-made interfaces, functions and modules. More than 3300 extensions are available for download under the GNU General Public License from a repository called the TYPO3 Extension Repository, or TER.
Visit : http://typo3.org
Drupal
Drupal is a free and open source modular framework and content management system (CMS) written in the programming language PHP. Like many modern CMSs, Drupal allows the system administrator to create and organize content, customize the presentation, automate administrative tasks, and manage site visitors and contributors.
Drupal is sometimes described as a “Content Management Framework” as its capabilities extend from content management to enabling a wide range of services and transactions. Although Drupal does offer a sophisticated programming interface, basic web site installation and administration can be accomplished with no programming.
Visit :http://drupal.org/
XOOPS
XOOPS is a free content management system, written in PHP, for websites. It uses a modular architecture allowing users to customize, update and theme their websites. XOOPS is released under the terms of the GNU General Public License (GPL) and is free to use, modify and redistribute.
Visit: http://www.xoops.org/
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