RichFaces was an open source Ajax-enabled component library for JavaServer Faces, hosted by JBoss.

It adds: RichFaces originated from the Ajax4jsf framework which Alexander Smirnov designed and implemented.

Ajax4jsf became an open-source project hosted on java.net, while RichFaces became a commercial JSF component library.

The framework is implemented as a component library which adds Ajax capability into existing pages, so a developer doesn't need to write any JavaScript code or to replace existing components with new Ajax widgets.

Hence, a developer can define the event on the page that invokes an Ajax request and the areas of the page that should be synchronized with the JSF Component Tree after the Ajax request changes the data on the server according to the events fired on the client.

Skinnability is a special feature of RichFaces that is used for defining common interface styles.