All Faces applications are standard Java web applications, as defined by the Servlet API. This means that they require an installed version of a standard servlet container (like Apache Tomcat, Jetty, or Resin) or a Java EE server (like IBM WebSphere, JBoss, or BEA WebLogic). JSF 1.1 requires a servlet container that supports version 2.3 of the Java Servlet specification or higher, and version 1.2 of the JavaServer Pages specification or higher. JSF 1.2 requires a container that supports Servlet 2.4 and JavaServer Pages 2.1 (you can, however, use Facelets instead of JSP).

Faces applications also require that you have installed an implementation of the framework. A JSF implementation is simply compiled Java code that adheres to the JavaServer Faces specification. There are two primary implementations -- Apache MyFaces and Mojarra, the reference implemenation (see our products directory for a full list). Java EE 5 containers include an implementation of JSF 1.2 by default.