Designing a web application? Familiarize yourself with Rich Internet Application technologies and the best UI controls for creating your application. Rich Internet Application technology has empowered us to create really amazing user experiences. The best RIAs on the web today rely on a discreet set of UI controls to provide a lively and timely experience. If you are moving from web site design to web application design, the best information you can have at your disposal is an understanding of these essential controls.