Q)What are JSP implicit objects?
=>In  a jsp, certain objects are (in fact, references of the objects)
available implicitly(automatically). They are known as JSP
implicit objects.
    For eg.
                 request (HttpServletRequest)
		 response (HttpServletResponse)
		 session (HttpSession)
		 application(ServletContext)  etc

For eg.
servlet
--------
doGet/doPost(HttpServletRequest request,HttpServletResponse response)
{
   ServletContext sc=getServletContext();
   sc.setAttribute("bal",50000);//data shared in application scope
   RequestDispatcher rd=request.getRequestDispatcher("view.jsp");
   rd.forward(request,response);
}
view.jsp
----------
BALANCE IS Rs. <%= application.getAttribute("bal") %>

Q)What are the things to be known about a method before calling it?

     1) Fully qualified name of the class/interface to which it belongs
     2) signature of the method
     3)return type of the method
     4)whether it is an instance method or a static method
     5)throws clause of the method
     6)access modifier

Q)What is  interface  object  in  Java?
 =>interface object means reference is interface  type  and object is its child class type.
 =>Some JDBC interfaces are 
                             Connection,Statement,ResultSet,PreparedStatement
=>JDBC interfaces provide driver vendor and DBMS vendor independency to
Java applications.
                  
=>Some Servlet API interfaces are 		   
		   ServletContext
                   ServletRequest
                   ServletResponse
                   HttpServletRequest
                   HttpServletResponse
                   HttpSession

=>Servlet API interfaces fecilitate Web container vendor independency

=>"Coding to interfaces is superior to coding to classes" as they promote loose
coupling.