A proxy is a stand-in — a server that acts on your behalf. On the web, it makes requests for pages instead of your device.
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The word "proxy" is direction-neutral. In law it means a person authorised to act for another; in networking it means a server authorised to make requests for another device. The mechanism is the same in both cases — one party stands in for another, taking the same action, but keeping the original party out of view. On the web specifically, a proxy is a computer that receives HTTP or HTTPS requests, forwards them to the real destination, and hands the response back. The destination sees the proxy, not the original client. There are many kinds of proxy — HTTP proxies for browser traffic, SOCKS proxies for arbitrary TCP, forward proxies that hide clients from servers, reverse proxies that hide servers from clients. A web proxy site like AnyProxy is a forward HTTP proxy dressed up as a website so it works without installation.
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