There are only 3 real good Content Management System (CMS) : Wordpress, Drupal and Joomla!
• Wordpress: Ideal for faily simple websites, such as blogs. Easy to manage. Large number of add-ons, mainly focused on blogs features.
• Drupal: Designed for advanced websites, having complex data organization, online stores, or platforms. Powerful.
So, why did we choose Joomla?
Able to do simple and advanced websites
Joomla has been designed to be able to do more than just blogs and slideshows. You can build complex websites easily, with powerful extensions and templates, including online stores features. It can do more than Wordpress, more easily than Drupal.
About 8000 thousand extensions!
July 25, 2016: 7918 extensions on the JED.
Many useful and powerful extensions are available to extend or customize your Joomla, a lot more than Drupal. These extensions are not mainly for blogs and photo galleries, such as in Wordpress, but provides a variety of tools! With Joomla, there is no limit to what you can actually do.
30 million downloads!
2.7% of the World websites are running Joomla! Already 30 million downloads, every 2.5 seconds.
Joomla is not first regarding popularity (Wordpress is), but it doesn't have to. Only Joomla is full featured.
A well organized backend
Joomla backend is well organized, making it easy for new and experienced users to add contents and organize it. Far superior to Wordpress.
Clean coding, rapid learning curve
Joomla is MVC based, whereas Wordpress is "function over function" based, which is a nightmare for the server load. Joomla structure allows developers to create their own extensions easily and overrides the Joomla core files without modifying them. How important that is to continue to enjoy the core updates!