Why Drupal CMS is a big League in contrast to variant CMS?

Content Management System- A Software tool that lets users add, publish, edit, or remove content from a website using a web browser on a smartphone, tablet, or desktop computer. 

Drupal CMS- This allows  developers to develop modules and applications using core library functions, with PHP as the primary programming language. Can be customized based on business needs.

In my session I would wish to share that why we should work with Drupal CMS than other also I would like to share my experience with the first CMS as Drupal.

• Drupal | The only CMS you need (after Netbeans 6 - The only IDE you need)
• Drupal | Authority Sites with ease
• Drupal | Hard to pronounce, even harder to explain
• Drupal | Drops make an ocean
• Drupal | Powerful, Flexible, Scalable Open Source Content Management
• Drupal | Empowering Web Construction
• Drupal | Plumbing Community
• Drupal | The Swiss Army Knife for Community Plumbing