Drupal is a open-source content management system (CMS) and content management framework (CMF) distributed under the GNU General Public License. Drupal allows you to build Web sites and easily organize, manage and publish your content, with an endless variety of customization. You get all the benefits of a CMS in managing your site. Drupal is used for every type of site from personal blogs to highly trafficked enterprise level sites. It is used as a back-end system 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. It is particularly well suited to e-Learning systems, Community/social networking sites, and news publishing, where its powerful authoring and publishing features allow administrators to create, revise, and deploy content in a rapid and organized manner.
The standard release of Drupal, known as Drupal core, contains basic features common to content management systems (similar to Joomla or Wordpress). It has a set of basic modules and themes intended to provide a foundation for deploying Drupal based websites. These include user account registration and maintenance, menu management, RSS feeds, page layout customization, and system administration. The Drupal core installation can be used as a brochureware website, a single- or multi-user blog, an Internet forum, or a community website providing for user-generated content. Drupal Core is easily extended with added modules and themes.
For specialized functionality there are thousands of free community-contributed addons, known as contrib modules, available to alter and extend Drupal's core capabilities and add new features or customize Drupal's behavior and appearance. Compared with Joomla's modules they are not the same. Drupal's modules are more like Joomla's components.
Drupal Themes are what determines the look and feel of Drupal sites. You can select a theme contributed by the community and customize it to suit your needs. You can also create your own themes. Themes are often created to suit a specific purpose or type of site. There are themes for News sites, corporate sites, Blogs, commerce sites and any more.
Because of this plug-in extensibility and modular design, Drupal is sometimes described as a content management framework. Drupal is also described as a web application framework, as it meets the generally accepted feature requirements for such frameworks.
Although Drupal offers a sophisticated programming interface for developers, no programming skills are required for basic website installation and administration. Programming is necessary only for developers in building custom modules.