* HTTP Router: Slim provides a fast and powerful router that maps route callbacks to specific HTTP request methods and URIs. It supports parameters and pattern matching. * Middleware: Build your application with concentric middleware to tweak the HTTP request and response objects around your Slim app. * PSR-7 Support: Slim supports any PSR-7 HTTP message implementation so you may inspect and manipulate HTTP message method, status, URI, headers, cookies, and body. * Dependency Injection: Slim supports dependency injection so you have complete control of your external tools. Use any Container-Interop container.

-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.