CMS [ Content management system ] is a web application designed to make it easy for any users to add, edit and manage a website.

Ccontent management systems help website users with content editing, they also take care of a lot of "invisible" work.
For example: CMS can generate navigation elements automatically, make the content searchable and indexable, keep track of users, their permissions and security settings.

Each listed CMS has open-source basis, runs on Apache + PHP (4 or 5) and require MySQL database.

Joomla CMS
Drupal CMS
OSCommerce CMS
Zen Cart CMS

Ecommerce Website Solutions
Social Networking Website Solutions
Dating Websites
Websites which features Blogs, Forums, Chatting, Messaging etc.