When you invoke a forward request, the request is sent to another
resource on the server, without the client being informed that a different
resource is going to process the request. This process occurs completly with in
the web container. When a sendRedirtect method is invoked, it causes the web
container to return to the browser indicating that a new URL should be
requested. Because the browser issues a completly new request any object that
are stored as request attributes before the redirect occurs will be lost. This
extra round trip a redirect is slower than forward.