Last week, we had the author of TDD for a Shopping Website LiveProject. Friday at 11am Ranch time, Steven Solomon will be hosting a live TDD session just for us. See for the agenda and registration link
Search is your friend: See this old thread In addition to that, a Servlet Container is just a specific type of Application Server which can host Java Servlets and conforms to some version of the Servlet API. Most Servlet Containers also have other features, of course.