Drupal is a free and open-source content management system. It is being used by around 2.1 % websites, ranging from personal blogs to corporate, political and government websites, all round the world.

Drupal contains all basic features common to content management systems. These include user account registration and maintenance, menu management, RSS feeds, page layout customization, and system administration. It can be used to support simple websites, blogs, forums or a community website providing for user generated content. Her eare the advantages of using Drupal:

Extremely Flexible: This robust and flexible platform can help you create both simple blogs with static pages and massive sites hundreds of dynamic pages which get millions of visitors.
Developer Friendly: Drupal is elementary in terms of installations and developers are motivated to create specific solutionsfor themselves. It offers a plethora of opportunities for developers.
SEO friendly: Drupal has been specifically created to be search engine friendly.
Enterprise Friendly: The software is capable of effortlessly managing thousands of pages of content. It is ideal for enterprise customers because of its Strong version control and ACL capabilities.
Highly stable: It holds strong even in the case of hundreds of thousands of visitors

Drupal comes with enumerable community contributed add-ons/modules which assist in enhancing and customizing basic Drupal functionalities as per your requirements. It offers a complex developing interface for developers but easy administrative framework which can easily be learned.