Drupal is open
Drupal was created over ten years ago and released as open-source software under the GNU Public License. That means it’s completely free to download, use, and modify: There are no purchase, license, or maintenance fees.
Drupal is web development
Drupal’s default installation is a database-backed web platform with file maintenance tools and a high level of security. Many developers take advantage of Drupal’s extensible architecture to go far beyond the “core” package.
Drupal is social