you get a request from the client and you send a response back to the client. client communicates what needs to done in the request and server gives the results of the request in the response. you use forward if you want another resource to handle a request and send response to the client. so if one of your servlets gets a request and you know that there is another servlet which should handle that request, you forward the request and response to that servlet (or a JSP or some other resource). you redirect when you want to send a temporary redirect response to the client using the specified redirect location URL.