The JSP engine plugs into a regular web server. When the web server forwards JSP page requests (i.e. pages ending in .jsp) to the JSP engine. The JSP engine then retrieves the .jsp file and parses it for embedded jsp processing commands. A JSP page contains HTML interspersed with JSP commands in between. Such commands often include calls to Java components or programs which are executed. The JSP commands in the page may then be replaced by their output. The result is a pure HTML page which is sent back to the web server which then returns to the client.