Difference between JSP and Servlet :
Jsp have implicit object but servlet are not.
Jsp is more convenient to write (and to modify!) regular HTML than to have a zillion println statements that generate the HTML.
jsp life is different from servlet.Jsp first translate into the servlet and after it compiled.
JSP page execution entity follow the Servlet Protocol.
Servlet is a pure java class..whereas jsp is not
Servlet is more faster than JSP, but JSP is more convenient than Servlet and JSP is clearly superior, shorter,
simple and easier to use.
Servlet is a Java class implementing the javax.servlet.
Servlets and Java Server Pages are complementary APIs, both providing a means for generating dynamic Web content.
Based on the situation we can decide.For example we are using Database related things(Opening a connection,executing statements etc.i.e, called as business logic)it is better to use Servelts(Re usability is possible with servlets but not with jsp's)Most of cases we use jsp's for presentation.i.e,the output nthat has to sent to browser can be done by making use of jsp's.
For read more information on JSP and Servlet visit to:http://www.roseindia.net/jsp/ http://www.roseindia.net/Servlets/