I'm not OP, but as they said, it's an HTTP proxy. Run it, then point your browser at http://localhost:8080 http://localhost:8080. The message is proxied over to

I'm not OP, but as they said, it's an HTTP proxy. Run it, then point your browser at http://localhost:8080 http://localhost:8080. The message is proxied over to http://httpbin.org http://httpbin.org (on port 80, the normal HTTP port). If you're in an overly restricted environment and have a legit need to proxy to a very limited set of hosts, you can ad-hoc make a proxy mapping from local port to a single specific remote host. Just change the 8080, destination host, and buffer file. And I mean this as encouragement, but you should read the synopsis from the GNU netcat manual. It's short and explains it well enough. netcat httpbin.org 80 is using connect mode, the -l one is using listen mode, and -p is --local-port (the port to listen on in listen mode).