Welcome to the world of JavaServer Faces. In this chapter, we will explain the core architecture of JavaServer Faces (JSF) and how the technology has evolved over the last few years. This chapter will make you aware of the ingredients of any JSF application and of the critical features added in JSF's major releases (1.0, 1.1, and 1.2). It will also explain the JSF life cycle and how a Struts developer can become a JSF developer.