Drupal is one of today's most popular open source content management systems. The open architecture of Drupal lets it function as a web development framework while maintaining ease of patch management in the face of customization. Drupal is backed by a large and active community. There exist a large number of extensions and the system is capable of supporting both MySQL and PostgreSQL.
Pros:
- Powerful & scalable
- Highly customizable
- Highly configurable
- Workflow controls
- Easier to maintain customized sites
- Excellent user access controls
- Longer development times
- Higher development expense