Quote:
I just plug it into the other room that the weak laptop is, and it extends the signal from the router automatically?

Not quite. You have to configure it using Apple's Airport Utility that is found in /Applications/Utilities. You have to specify the network it is to join along with the network password and what you want it to do when it joins the network (Extend the network).

If we knew what it was we were doing, it wouldn't be called research, would it?

— Albert Einstein