proxy servers - Definition from the Hotspot Shield Glossary
A proxy server is a server that bridges the gap between a client and a physical server. In essence, it acts as a middleman between a client and server and filters out any information that it can sort itself.
Proxy servers are useful for directing traffic, filtering server requests, and improving the performance of a network. Proxy servers will store requests in their cache for a set amount of time. This can reduce server traffic instead of forwarding every new request onto the main server, the proxy can check through its cache and if it has the request, can directly return it to the client. Furthermore, proxy servers can filter server traffic and allow clients limited access to a network or website for example.