Stunters tend to use lightweight crotch rocket motorcycles in order to do their stunts, because they are easy to toss around (primarily because of their weight).
Typical stunter tricks are wheelies, which entails leaning to the rear of the bike while accelerating in order to lift the front wheel off of the ground and maintain rear wheel balance for as long as possible (also known as a 'catwalk'). Also popular is the stoppie, which is where the motorcycle's front brake lever is pulled while the rider leans forward, bringing the bike to a stop with the rear wheel off the ground (eventually it must fall back down though).
Despite how 'cool' stunters may seem, many of them choose to perform such acts on public roads and highways. This is not only VERY dangerous for themselves and the other riders and cagers around them, but this also consequently causes insurance rates for motorcyclists to be as high as they are. Stunting is a huge factor in the enormous insurance costs for bikes all over North America.