The primary use of a proxy server is to concentrate all internal clients into a single outgoing connection. Thus the proxy will be representing all internal users towards the Internet. One popular technique is proxy caching, in which one or more computers act as a cache of documents for a set of WWW clients. These clients are configured to send HyperText Transport Protocol (HTTP) requests to the proxy. If possible, the proxy serves the requests from its cache. Otherwise, the proxy forwards the request to the content provider, that is, to the server containing the source copy of the requested data.