Wow, those are some very fundamental questions. My suggestion is to pick up one of the following books: JBoss at Work: http://www.jbossatwork.com/ JBoss - http://www.oreilly.com/catalog/jbossadn/ Both books describe how to go about developing applications for use within JBoss. You might also want to pick up a book on JSPs/Servlets. Some free ones are online (though they are somewhat dated). http://pdf.moreservlets.com/ And possibly also a book on EJB3 development, there are quite a few available now, here is one: http://www.oreilly.com/catalog/entjbeans5/ To answer your specific questions: 1) A web server has a JSP/Servlet container and implements only parts of the Java EE spec, while an application server has an EJB container and implements the full Java EE spec. 2) See the books I recommended. 3) Yes, see the books. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4050535#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...