Most everything uses either USB or Firewire these days. Which is a god-send considering the mess that used to be present...
The biggest concern that he will have is getting the proper power adapters for the equipment.
As for what they stand for or refer to, USB stands for Universal Serial Bus and Firewire is Firewire... USB is the rectangular connection on the computer side and the square with two clipped corners on the device side, or a smaller retangularish interface on the device side... Firewire basically looks like a really skinny tall house on it's side on the computer end, and it can have the same end on the device side or a much smaller interface on the device side as well...