Drupal is an open-source and free Content Management System or CMS. Drupal is accredited by the GNU General Public License and is implemented in PHP. It is utilized as the back-end system in most of the websites all over the world starting from individual blogs to bigger corporate as well as political websites such as data.gov.uk, and whitehouse.gov. Drupal is also applied in business collaborations and knowledge management.

The standard format of Drupal is known as Drupal core. It contains the basic features found in most of the CMSs. The features include menu management; user accounts registration as well as maintenance, page layout customizations, system administration and RSS-feeds. The Drupal core system can also be used like a multi or single-user blog, as Internet forum, as any brochureware website or any community website for user-generated contents.

You can use more than 5800 free community-contributed modules to extend and alter the capabilities of Drupal core and add novel features and customize Drupal’s appearance and behavior. For this modular designs, Drupal is described as the Content Management Framework.