Java Server Pages( JSP).

The 'official' Java technology for generating web pages from Java. JSP pages are automatically compiled into Java servlets, and therefore have some relationship to XSP pages. Both technologies:

• Consist of a mixture of program code and markup
• Are compiled into a binary form (Java class) for execution
• Allow the creation of custom tag libraries
  

However there are differences:

• XSP pages can be written in multiple languages (e.g. Javascript as well as Java). JSP is Java only.
• XSP pages generate dynamic data for feeding into Cocoon Pipelines where it is subsequently processed, while JSP is a presentation layer technology which formats the results of processing for the user.
  

JSP 1.2 defines a mandatory well-formed XML syntax for JSP pages (previously to this, it was optional).