* Symfony Framework: The leading PHP framework to create websites and web applications. Built on top of the Symfony Components. * Symfony Components: A set of decoupled and reusable components on which the best PHP applications are built, such as Drupal, phpBB, and eZ Publish. * Symfony Community: A huge community of Symfony fans committed to take PHP to the next level. * Symfony Philosophy: Embracing and promoting professionalism, best practices, standardization and interoperability of applications.

-Model-View-Controller (MVC) design pattern. -Database Access Objects (DAO), Query Builder, Active Record, DB Migration. -AJAX-enabled widgets. -Authentication and authorization. -Yii is equipped with many security measures to help prevent your Web applications from attacks such as SQL injection, cross-site scripting (XSS), cross-site request forgery (CSRF), and cookie tampering. -Yii supports data caching, page caching, fragment caching and dynamic content.