Technically speaker, Parkour is a French-based "art" developed to help one navigate an environment from one point to another, using the capabilities of the human body. Artistically speaking, it is not "an expression, a method, or religion", but rather a method by which one trains the body to overcome [literal] obstacles in the most efficient ways possibles. Most often practiced in urban settings, parkour enthusiasts employ skills such as jumping and climbing with the goal of transportation exclusively via the human body and surrounding objects.

Traditionally, parkour was exclusively dudes and girls, and was a practice arguably introduced into the mainstream psyche when an MTV show profiled "freestyle walking" in the mid-nineties.

Things, of course, have changed since then. The Sharper Image went bankrupt, Monica Lewinsky probably doesn't shop at The Gap anymore, and parkour is something anyone can do now, even dogs.

Enter Roxy, a Thai Ridgeback mix from Hawaii who can scale walls with the best of 'em: