I think it maps pretty well to networking as a whole.
Maybe you could try to read a paper or watch a tutorial about that?
It would be very lengthy to explain it in a post here and I don't know how many people would have the spare time to do that. Anyway, you're basically sending
packets between different programs (that may be run on different computers). This allows you to transfer data between them. That is the basic idea of it, but I guess you already knew as much

So the point is to figure out what data you need to send / receive to give the same view of a world for instance to all connected players. Or whatever you're planning on doing.
"Why do programmers get Halloween and Christmas mixed up?" Because Oct(31) = Dec(25)