Xoops is an easy to use dynamic web content management system written in PHP.
XOOPS is an acronym of eXtensible Object Oriented Portal System. Though started as a portal system, XOOPS is in fact striving steadily on the track of Content Management System. It can serve as a web framework for use by small, medium and large sites.
XOOPS is released under the terms of the GNU/GPL license and is free to use and modify.