what is proxy,proxy server

In computer networks, a proxy server is a server (a computer system or an application) that acts as an intermediary for requests from clients seeking resources from other servers. A client connects to the proxy server, requesting some service, such as a file, connection, web page, or other resource available from a different server and the proxy server evaluates the request as a way to simplify and control their complexity. Today, most proxies are web proxies, facilitating access to content on the World Wide Web.

some proxy sites:
 http://www.unblock-proxy.net/
http://www.hidemyass.com/proxy/