Drupal

Drupal ( /ˈdruːpəl/) is a free and open-source content management framework (CMF) written in PHP and distributed under the GNU General Public License. It is used as a back-end system for at least 2.1% of all websites worldwide ranging from personal blogs to corporate, political, and government sites including whitehouse.gov and data.gov.uk. It is also used for knowledge management and business collaboration.