Akkam's Razor TL;DR.

Street pickpockets generally work in teams, known as whiz mobs or wire mobs. The “steer” chooses the victim, who is referred to generically as the “mark,” the “vic,” or the “chump,” but can also be categorized into various subspecies, among them “Mr. Bates” (businessman) and “pappy” (senior citizen). The “stall,” or “stick,” maneuvers the mark into position and holds him there, distracting his attention, perhaps by stumbling in his path, asking him for directions, or spilling something on him. The “shade” blocks the mark’s view of what’s about to happen, either with his body or with an object such as a newspaper. And the “tool” (also known as the “wire,” the “dip,” or the “mechanic”) lifts his wallet and hands it off to the “duke man,” who hustles away, leaving the rest of the mob clean. Robbins explained to me that, in practice, the process is more fluid—team members often play several positions—and that it unfolds less as a linear sequence of events than as what he calls a “synchronized convergence,” like a well-executed offensive play on the gridiron.

Fascinating article on pickpockets in the New Yorker.