Forward pass

In several forms of football a forward pass is a throwing of the ball in the direction that the offensive team is trying to move, towards the defensive team's goal line. The forward pass is one of the main distinguishers between gridiron football (American football and Canadian football) in which the play is legal and widespread, and rugby football (union and league) from which the North American games evolved, in which the play is illegal.

In some football codes, such as association football (soccer), the kicked forward pass is used so ubiquitously that it is not thought of as a distinct kind of play at all. In these sports, the concept of offside is used to regulate who can be in front of the play or be nearest to the goal. However, this has not always been the case. Some earlier incarnations of football allowed unlimited forward passing, while others had strict offside rules similar to rugby.

The development of the forward pass in American football shows how the game has evolved from its rugby roots into the distinctive game it is today. Illegal and experimental forward passes had been attempted as early as 1876, but the first legal forward pass in American football took place in 1906, after a change in rules. Another change in rules occurred on January 18, 1951, which established that no center, tackle, or guard could receive a forward pass. Today, the only linemen who can receive a forward pass are the ends. Current rules regulate who may throw and who may receive a forward pass, and under what circumstances, as well as how the defensive team may try to prevent a pass from being completed. The primary pass thrower is the quarterback, and statistical analysis is used to determine a quarterback's success rate at passing in various situations, as well as a team's overall success at the "passing game."

In American and Canadian football, a forward pass, usually referred to simply as a pass, consists of a player throwing the football towards the opponent's goal line. This is permitted only once during a scrimmage down by the offensive team before team possession has changed, provided the pass is thrown from in or behind the neutral zone. An illegal forward pass can incur a yardage penalty and the loss of a down, although it may be legally intercepted by the opponents and advanced.

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