The snap, sometimes called a hike, in football is a backward pass from the center to the quarterback to begin play on a down. The center, an offensive lineman, throws the ball through his legs into the hands of the quarterback, who is either standing directly behind the center or a few yards in the offensive backfield. It is an illegal snap to pass the ball around the side of the hip.
The snap begins the moment the center moves the ball in a backward motion. The center is not allowed to fake the snap in an attempt to get the defense to jump offsides, or the offense will be penalized with a false start penalty. The moment the snap begins, play may commence and players on both the offense and defense may move past the line of scrimmage. After a play ends, the next down in the down cycle begins and a snap will commence the next set of play.
The snap takes place on every line of scrimmage during any point in the game and it starts every new down.