Drupal is an open-source content management system (CMS) that allows users to build and manage websites. It provides features like blogs, galleries, and the ability to restrict content by user roles. Drupal is highly customizable through modules and themes and supports moving sites between development, test, and production environments. While it uses some technical terms like "nodes" and "taxonomy," Drupal is accessible to non-developers and can be installed on common web hosting with Apache, MySQL, and PHP. Resources for learning Drupal include books, training videos, online communities, and conferences.