Memes

It's basically a power strip:

but specifically for cables that carry Internet traffic instead of electrical power.

A more direct analogy would be a telephone switchboard (which is why it is called a "switch"), basically a computerized version of those old-timey operator ladies who used to sit in a room waiting for you to make a phone call, and they'd physically move a plug connected to your phone and plug it directly into the phone line of whoever you were trying to call. That, but for computers trying to talk to one another over network cables instead of making telephone calls.