Wylie asked what a wifi signal was. Wifi rules!! It's a wireless internet connection which is like a radio signal that projects over short distances (a few hundred yards). You can access it with a special card on a laptop, or similarly set up accessories to broadcast and receive a signal on your home computers. That way at home you can use wifi to connect up more than one computer to one incoming signal (like from a hardwired cable connection).
On the road you can sometimes access wifi signals at places that broadcast them (usually as a sort of marketing gimmic or add-on service) like coffeeshops, truckstops, hotels, campgrounds, marinas, etc. and pick up a free Internet connection (or pay a nominal fee in some places). Right now I'm picking up a signal from some nearby neighbor's house.
The problem is that the signals don't transmit very far, so they only work within a few hundred feet of whatever is broadcasting them, and can be kind of flaky. But when you're traveling, wifi is the best way to go!