The document introduces Drupal, an open source content management system (CMS). It discusses Drupal's architecture including the Apache web server, PHP scripting language, and MySQL database. It provides instructions on downloading and installing Drupal, creating sample content, and getting started with content management, comments, and the user interface. The document also outlines additional Drupal features covered in future sessions such as Views, CCK, taxonomy, multimedia support, theming, social networking, and PHP module development.