Drupal

Drupal is one of the most versatile open source content management systems on the market. Over a thousand developers contributed to the code in the most recent version. Drupal is built for high performance and is scalable to many servers, has easy integration via REST, JSON, SOAP and other formats, and features a whopping 15,000 plugins to extend and customize the application for just about any type of website. You won’t feel alone if you use Drupal; the hundreds of thousands of Drupal users around the world have built a very robust community with local meetups and global user conferences.

Features:

• Use Drupal to tell the world about yourself, your company and your work. Modules are available to easily add photo galleries and support social media and it's easy to create a theme that reflects your personality and style.
• Drupal is used by large, well-known websites, including those belonging to the University of Oxford and the White House. It includes professional content management and collaboration tools and is scalable to high workloads.
• Drupal can power an e-commerce website. Modules are available for payment and shipping integration, notifications, order management and shopping cart workflows, and it's easy to find or develop themes for online storefronts.