intermediaries between end users and Web sites such as ISPs, commercial online services, and corporate networks. Proxy servers hold the most commonly and recently used content from the Web for users in order to provide quicker access and to increase server security.
a server that are in a different country than the country the user is in
A system that caches items from other servers to speed up access. On the Web, a proxy first attempts to find data locally, and if it's not there, fetches it from the remote server where the data resides permanently.
Proxy servers enable two networks to stay disparate for all functions except those that have a specific proxy to move information between the two networks. Proxy Server are generally used when the majority of traffic on a network is local to that network, and there are only a few well defined times that traffic should move between networks.
are used by ISPs and other organizations to save bandwidth. Proxy servers can intercept requests and check to see if they hold a copy of the requested resource in cache. If the proxy server does has a copy it will send this back instead of passing the request on. This can sometimes lead to "stale" (out of date) versions of pages being served up instead of more recent versions.