Proxy Server, English name is proxy server. Generally speaking, there are three functions for ordinary netizens.

First of all, through it, we can visit some websites that we can't usually go to.

The second is to speed up our browsing of some websites through it.

The third is to connect the Internet and intranet as a firewall.

The port number is the port of the proxy server, which is usually bound to ports 80, 3 128 and 8080 of the proxy server.