I used to do tech support for non tech savvy people and couldn’t use the jargon, so I got good at giving enuf info to know how things work without bogging them down in terminology, terminology is scary for some people. Answering like another did further down would require me to actually dig in my brain, and would illicit a confused dog look from my old clients, but what they said about the OSI layers is the real answer.

More like the bouncer. It communicates with the outside world, ensures the correct device inside your network talks to its intended outside network (NAT), and several other things that I have forgotten.