"Servlet" is an interface. "GenericServlet" inherits from "Object" and implements "Servlet". "HttpServlet" inherits from "GenericServlet". You can read the J2EE API documentation at http://java.sun.com/j2ee/j2sdkee/techdocs/api/index.html for more information. If that doesn't answer you question, go to java.sun.com and look for tutorials on J2EE and/or servlets.
CJP (Certifiable Java Programmer), AMSE (Anti-Microsoft Software Engineer)
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