Drupal is an open source content management platform, allowing an individual or a community of users to easily publish, manage and organize a great variety of content on a website.
Equipped with a powerful blend of features, Drupal is able to support community sites, blogs, portals and more.
This is Drupal's core, you can find the contributed modules page at http://ohloh.net/projects/3502.
These details are provided for information only. No information here is legal advice and should not be used as such.