There are a number of things Apache can do that Tomcat can't. E.g., running PHP or other non-Java server programs, or using the multitude of modules that enhance Apache in other ways.
In days past it used to be that people used Tomcat purely for servlets/JSP, and let Apache handle the static content, but Tomcat has become much faster at serving static content since then, so that alone is no longer a good reason to use Apache in addition to Tomcat.
Joined: Nov 29, 2005
Thanks Ulf for your reply. If in my web application there are some php's (and want the php's to be processed by apache) ,so for this any special configuration is required to be done apart from mod_jk.
For this do I have to deploy one application with php's in apache and other with the same context name in tomcat for servlets.