1. A method for delivering an incomplete response from a Hypertext Transfer Protocol (HTTP) server to a client, comprising: receiving a file request in the HTTP server from the client, wherein the file request indicates whether the client is capable of using an incomplete response; determining in the HTTP server, based on the file request, whether the client is capable of using an incomplete response; and sending from the HTTP server to the client an incomplete response in response to determining that the client is capable of using an incomplete response if a full response is not available at the HTTP server.