A J2EE server incorporates web container and EJB container. The web container has the web components
(Servlet + JSP ).
The EJB container has the business components.
A web server has only Web container. Apache is the web server and Tomcat is the web container
There is no stand alone EJB containers now a days.
J2EE servers are WebService , JBoss which has both web and EJB containers.
