What exactly does the Heartbeat command do?

My friend mentioned how the heartbeat command is useful for something (I don’t remember i was a few motnhs ago)

I typed in “heartbeat” a few days ago at my server, but nothing happens. So I typed in “Help heartbeat” it said that heartbeat “initiates a heartbeat on the server” I don’t see why you would use the name of a console command to describe the command. So can anyone explain what it does?

That command displays the game server to the list of Steam internet servers.