参考：http://www.journaldev.com/1854/java-web-application-tutorial-for-beginners#web-server-client
Web Server and Client
HTML and HTTP
Understanding URL
Why we need Servlet and JSPs?
First Web Application with Servlet and JSP
Web Container
Web Application Directory Structure
Deployment Descriptor
原文：http://www.cnblogs.com/xkxf/p/6843403.html