The Java EE 7 Tutorial
This chapter introduces the Expression Language (also referred to as the EL), which provides an important mechanism for enabling the presentation layer (web pages) to communicate with the application logic (managed beans). The EL is used by both JavaServer Faces technology and JavaServer Pages (JSP) technology. The EL represents a union of the expression languages offered by JavaServer Faces technology and JSP technology.
The following topics are addressed here: