프록시 서버(A server located on a network between client software, such as a Web browser, and another server. It intercepts all requests to the server to determine whether it can fulfill them itself. If not, it forwards the request to another server)
A server that acts on behalf of a user(Typical proxies accept a connection from a user, make a decision as to whether the user or client IP address is permitted to use the proxy, perhaps perform additional authentication, and complete a connection to a remote destination on behalf of the user)
