Offensive formations

The goal of the offense is, most commonly, to score points. In order to accomplish this goal, coaches and players plan and execute plays – based on a variety of factors: The players involved, the opponent's defensive strategy, the amount of time remaining before halftime or the end of the game, and the number of points needed to win the game. Strategically, the offense can prolong their possession of the ball to prevent the opponent from scoring. Offensive scoring chances, or drives, end when they cannot move the ball 10 yards or the ball is turned over via fumble or interception.

On offense, there are three types of players: linemen, backs, and receivers. These players' positions and duties on the field vary from one offensive scheme to another.

The position names (as well as the abbreviations recognized by coaches, players, and fans) vary from one team's playbook to another, but what follow are among the most commonly used:

(This is understood to be players on the line other than at the ends; also referred to as "interior linemen". The ends—i.e., the players at the ends of the line—are discussed below under "Receivers".)

Backs are so named because they line up behind (in back of) the line of scrimmage at the start of the play.

(Eligible receivers are the ends and the backs, other than an NFL quarterback lined up "under center". Not all backs fall into the wide-receiver category below.)

Before the ball is snapped the offensive team lines up in a formation. The type of formation used is determined by the game situation. Teams often have "special formations" that they only use in obvious passing situations, short yardage, goal line situations, or formations they have developed for that particular game just to confuse the defense. There are a nearly unlimited number of possible formations – a few of the more common ones are:

When the team is in formation and the quarterback gives a signal, either by calling out instructions or giving a non-verbal cue (a so-called "silent count"), the center snaps the ball to the quarterback and a play begins.

A running play occurs when the quarterback hands the ball to another player, who then attempts to carry the ball past the line of scrimmage and gain yards, or the quarterback keeps the ball himself and runs beyond the line of scrimmage. In both cases, the offensive line's main job is to run block, preventing the defensive players from tackling the ball carrier.

The choice of running play depends on the strengths of an offensive team, the weaknesses of the defense they are opposing, and the distance needed to score a touchdown or gain a first down. There are many kinds of running plays, including:

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