What is Drupal?

Drupal is a free and open source framework and Content Management System (CMS) written in PHP.

Drupal can run on any computing platform that supports:

* a web server capable of running PHP (version 4.3.5+), including Apache, IIS, Lighttpd, and nginx.
* a database, such as MySQL or PostgreSQL, to store content and settings.

Although Drupal is often described as a "content management system" (CMS) it is also a "content management framework" (CMF). In other words, unlike a typical CMS, it is geared more towards configurability and customization.