Drupal is a free software package that allows an individual or a community of users to easily publish, manage and organize a wide variety of content on a website. Tens of thousands of people and organizations are using Drupal to power scores of different web sites, including

• Community web portals
• Discussion sites
• Corporate web sites
• Intranet applications
• Personal web sites or blogs
• Aficionado sites
• E-commerce applications
• Resource directories
• Social Networking sites

The built-in functionality, combined with dozens of freely available add-on modules, will enable features such as:

• Electronic commerce
• Blogs
• Collaborative authoring environments
• Forums
• Peer-to-peer networking
• Newsletters
• Podcasting
• Picture galleries
• File uploads and downloads

and much more.

Drupal is open-source software distributed under the GPL (“GNU General Public License”) and is maintained and developed by a community of thousands of users and developers. If you like what Drupal promises for you, please work with us to expand and refine Drupal to suit your specific needs.

Demo: http://php.opensourcecms.com/scripts/details.php?scriptid=191
Themes: http://drupal.org/project/Themes
Modules: http://drupal.org/project/Modules

Price: Free- Open Source
Installation: You need to install yourself.
Trial Version: free
Support: Forums
Required Software: PHP, mysql
Description:With many modules (extra add on features), such as blogs, voting, and reviews, Drupal is a very good basic CMS system.

Beginners with some PHP knowledge can install, but for customization, I recommend it for intermediate and advanced users.

Drupal Web Site Examples;

Drupal Admin Panel: