What it is

The pocket is the protected area around the quarterback that the offensive line forms when he drops back to pass.

In a game

A pocket collapses when pass rushers push the blockers back. A quarterback must sense the pressure and step up or move out of it.

More detail

Offensive lines shape the pocket either as a cup, which curves around the quarterback, or as a slide, which moves the whole line in one direction. A quarterback can also move the pocket: on a rollout or a sprint-out he leaves the middle, and the line blocks in a new direction.

Animated diagram

1. The quarterback takes the snap and drops back a few steps.
2. The five linemen step back and make a curve, a pocket, around him.
3. The pass rushers are pushed around the edge of the pocket, which gives the quarterback a few seconds to find a receiver.