Where to Go Next

The Java Servlet Technology page at http://java.sun.com/products/servlet/

The Java EE 5 Tutorial at http://java.sun.com/javaee/5/docs/tutorial/doc/

The Apache Tomcat 7.0 Documentation at http://tomcat.apache.org/tomcat-7.0-doc/index.html

And of course, search for "servlets", "cgi" and "cgi vs servlets" using your favorite Web search engine.