Have you heard of it? The definition, according to Wikipedia.com is:
"Parkour is the non-competitive sport originating in France of traversing mainly urban landscapes by running, climbing and jumping. Participants run along a route, attempting to navigate obstacles in the most efficient way possible, using only their bodies. Skills such as vaulting, rolling, swinging and wall scaling are employed. Parkour can be practiced anywhere, but areas dense with obstacles are preferable and it is most commonly practiced in urban areas."