What is the difference between Web server and Application server?
Web server is designed to serve HTTP content whereas Application server is not limited to HTTP response but also can serve other request.
Application server supports distributed transaction and EJB whereas web server only supports servlet and JSP.
Application server can contain web server in them. For example :- JBoss, WAS
Application server provides following features over web server :-
To read more visit Tomcat-web server or application-server