Parkour, a made-up word, cousin to the French parcours, which means “route,” is a quasi commando system of leaps, vaults, rolls, and landings designed to help a person avoid or surmount whatever lies in his path — a vocabulary, that is, to be employed in finding one’s way among obstacles.

Parkour goes over walls, not around them; it takes the stair rail, not the stairs. Spread mainly by videos on the Internet, it has been embraced in Europe and the United States by thrill seekers and martial-arts adepts, who regard it as part extreme sport — its founder would like to see it included in the Olympics — and part gruelling meditative pursuit.

Movies like its daredevil qualities. A bracing parkour chase begins “Casino Royale,” the recent James Bond movie. It includes jumps from the boom of one tower crane to that of another, but parkour’s customary obstacles are walls, stairwells, fences, railings, and gaps between roofs — it is an urban rather than a pastoral pursuit. The movements are performed at a dead run. The more efficient and fluid the path they define, and the more difficult and harrowing the terrain they cross, the more elegant the performance is considered by the discipline’s practitioners.