1. We can use HttpServlet as a base class to develop http based servlets.
  2. It is the child class of GenericServlet
  3. HttpServlet

  4. For every http method XXX,HttpServlet contains the corresponding doXxx() method.
  5. protected void doXxx(HttpServletRequest req,HttpServletResponse resp)
       throws ServletException,IOException
    

    Example:

    protected void doGet(HttpServletRequest req,HttpServletResponse resp)
       throws ServletException,IOException
    
  6. HttpServlet contains 2 service methods,one is public and the other is protected.
  7. public void service(ServletRequest req,ServletResponse resp)
    throws ServletException,IOException
    
    
    protected void service(HttpServletRequest req,HttpServletResponse resp)
    throws ServletException,IOException