Drupal is a free and open source content-management framework written in PHP and distributed under the GNU General Public License. Drupal provides a back-end framework for at least 2.3% of all sites worldwide – ranging from personal blogs to corporate, political, and government sites. Systems also uses Drupal for knowledge management and for business collaboration. , the Drupal community is made up of 1.3 million members, including 109,800 users and 39,500 free modules. Drupal functionality, over 2,570 free themes that change the look and feel of Drupal, and at least 1,200 free distributions that allow users to quickly and easily set up a complex, use-specific Drupal in less steps. The standard release of Drupal, known as Drupal core, contains basic features common to content-management systems. These include user account registration and maintenance, menu management, RSS feeds, taxonomy, page layout customization, and system administration. The Drupal core installation can serve as a simple Web site, a single-or multi-user blog, an Internet forum, or a web site providing for user-generated content. Drupal also describes itself as a Web application framework. When compared with notable frameworks Drupal meets the requirements of such web frameworks. Although Drupal offers a sophisticated API for developers, it does not require programming skills.