This article needs additional citations for verification .(January 2013)
A snap (colloquially called a "hike", "snapback", or "pass from center") is the backward passing of the ball in gridiron football at the start of play from scrimmage.
The ball begins on the ground with its long axis parallel to the sidelines of the field, its ends marking each team's line of scrimmage in American football; in Canadian football, the line of scrimmage of the team without the ball is 1 yard past their side of the ball. The player snapping the ball (known officially as the "snapper" in rule books) delivers the ball to another player, and that action is the snap. The snapper may hand, throw, or even roll the ball to the other player. The snap must be a quick and continuous movement of the ball by one or both hands of the snapper, and the ball must leave the snapper's hands. The various rules codes have additional requirements, all of which have the effect of requiring the ball to go backward. The snapper almost always passes the ball between his legs, but only in Canadian football is that required.
In the standard gridiron football formation, the center/centre is the snapper and is situated in the middle of the line of scrimmage. Only in arena football is the center required by rule to be the snapper. In other codes, a guard, tackle, tight end or split end can legally deliver the snap; such scenarios, known as an unbalanced line, are seldom used outside of trick plays and novelties.
For a handed snap, the snapper will usually have his head up, facing opponents. For a thrown snap, especially in formations wherein the ball may be snapped to players in different positions, the snapper will commonly bend over looking between his legs. Because of the vulnerability of a player in such a position, the National Collegiate Athletic Association (NCAA) and the National Federation of State High School Associations ("Fed") have adopted rules providing that if a player is positioned at least 7 yards behind the neutral zone to receive a snap, opponents are not to deliberately contact the snapper until one second after the snap (NCAA), or until the snapper has a chance to react (Fed). However, in professional football it is common for a center to be able to practice a single "shotgun" formation thrown snap enough to keep his head up and toss it blindly.
A snap is considered a backward pass, therefore if the ball is snapped and it hits the ground without any player gaining control of the ball the play is ruled as a fumble.
The team entitled to snap the ball will usually know in advance the moment when the snap is to occur as one of their players calls out signals, which usually include a loud sound such as "hut" voiced one or more times, the number of which they know; they are thus said to know the "snap count". Therefore, they have a considerable advantage over their opponents. The Center is not, however, allowed to make motions simulating part of the snap-action; therefore their opponents can be confident the first motion of the ball or the Center's hands is the beginning of the snap.
The snap count is decided on in the huddle, usually expressed as "...on <number>." being the final words spoken by the quarterback after calling the play but before the huddle breaks and the players go to the line of scrimmage. The snap count allows offensive players to have a small head start. The defensive players want to predict the snap, and build up speed such that they cross the line of scrimmage exactly as the play begins, to increase their chances of getting a tackle for a loss or a sack. By varying the snap count, a quarterback forces the defensive players to react to the movement of the offensive players, or risk being called for an offsides or encroachment penalty. Unfortunately for the offense, this advantage can sometimes become a disadvantage. When faced with an exceptionally loud stadium, players may be unable to hear the snap count and are forced to concentrate more on visual cues (silent snap count or a hard count), or risk false start penalties.
The offense must also be mindful of the play clock. If they fail to snap the ball in time they incur a delay of game penalty. Also, with a dwindling play clock, the defense has better chances of guessing when the ball will be snapped. It is easier to predict when the ball will be snapped with 2 seconds left on the play clock, rather than 5 seconds.
The defensive team is not allowed to simulate, by calling out numbers, the offense's snap count. Successfully simulating the count would cause members of the offensive team to act too early ruining co-ordination of the play and inviting penalties. Current rules, unlike earlier rules, position officials so far from the line of scrimmage for 50 minutes of the 60-minute game that it is extremely difficult to hear if the defense is simulating the count.
The snap, the set scrum and ruck in today's rugby union, and the play-the-ball in rugby league have common origins in rugby football. As the rules of rugby's scrimmage were written when the game came to North America, they had a significant flaw which was corrected by custom elsewhere, but by the invention of the snap-in American football.
The rule adopted by a committee for American football in 1880 first provided for the uncontested right of one side to play the ball by foot (in any direction) for a scrimmage. A certain use of the foot on the ball which had the same effect as heeling it back was known as a "snap". Later in the 19th century, the option of snapping the ball back by hand was added. The option to play the ball with the foot was preserved, however, for several decades, although by early in the 20th Century it was restricted to kicking the ball forward. The kick forward in scrimmage was a surprise play that did not work against a prepared defense. Also for several decades alternatives to the scrimmage for playing the ball from across the sideline after it had gone out of bounds—a throw-in or "fair", and "bounding in"—existed. Until well into the 20th century, rather than an official readying the ball for scrimmage, the side entitled to the snap had complete custody of the ball and could snap it from the required spot at any time; for instance, a tackled ball carrier might feign injury, then suddenly snap the ball while recumbent, there being no stance requirement yet. The neutral zone and the right of the Center not to be contacted by an opponent before the snap also was not an original feature. As the 20th Century drew to a close, the NCAA and National Federation of State High School Associations extended that protection to some time after the snap, in cases where a player is positioned at least 7 yards deep to receive a thrown snap.
Canadian football used the rugby scrimmage unaltered until near the end of the 19th century, when, regionally at first, under the influence of the American scrimmage, the number of players in the scrimmage was limited to three—a "centre scrimmager" bound on either side by props called "side scrimmagers". The centre scrimmager was later renamed the "snap", and in intercollegiate play one side was given the right to put foot to ball first. Beginning regionally again and universally by 1923, the Burnside rules led to the 3-man scrimmage being reduced to the centre alone, the number of players on the field being reduced commensurately from 14 to 12, and a snap rule and neutral zone similar to that of American football was adopted. In addition to the between-the-legs requirement noted above, for several years after the adoption of the hand snap, a hand-to-hand snap was illegal, the ball required to be thrown instead, in Canadian football. (Though it was technically legal, the hand-to-hand snap was not used on the American side of the border until the 1930s.) Apparently, a complete break was desired from system of backheeling, and the T formation having gone into eclipse in American football at the time, the Canadian snap was modeled on the formations then in common use in the US, such as the single wing.
The game design rationale for requiring the snap to be a quick and continuous motion to the backfield is to eliminate the need for rules provisions for a live ball in scrimmage. In Rugby Union the ball may be retained by the forwards and played for a time via the foot in a scrummage (which Rugby League has as well) or ruck, or by the hands in a maul, necessitating additional restrictions on play and player positioning during those intervals. In American and Canadian football, the ball as it is put in play is only held in the line (by the Center) for a fraction of a second. The uncontested possession also, as Walter Camp pointed out, allows for better offensive and defensive planning by the side entitled to snap the ball and their opposition, respectively. A muffed snap can be recovered by either team.
Canadian football is a sport played in Canada in which two teams of 12 players each compete for territorial control of a field of play 110 yards (101 m) long and 65 yards (59 m) wide attempting to advance a pointed oval-shaped ball into the opposing team's scoring area.
In gridiron football, not all players on offense are entitled to receive a forward pass: only an eligible pass receiver may legally catch a forward pass, and only an eligible receiver may advance beyond the neutral zone if a forward pass crosses into the neutral zone. If the pass is received by a non-eligible receiver, it is "illegal touching". If an ineligible receiver is beyond the neutral zone when a forward pass crossing the neutral zone is thrown, a foul of "ineligible receiver downfield" is called. Each league has slightly different rules regarding who is considered an eligible receiver.
In gridiron football, a line of scrimmage is an imaginary transverse line beyond which a team cannot cross until the next play has begun. Its location is based on the spot where the ball is placed after the end of the most recent play and following the assessment of any penalty yards.
Touch football is an amateur variant of American football and Canadian football in which the basic rules are similar to those of the mainstream game, but instead of tackling players to the ground, the person carrying the ball need only be touched by a member of the opposite team to end a down. It is similar to street football, another amateur variant, however in street football full contact is allowed.
Gridiron football, also known as North American football or, in North America, simply football, is a family of football team sports primarily played in the United States and Canada. American football, which uses 11-player teams, is the form played in the United States and the best known form of gridiron football worldwide, while Canadian football, featuring 12-player teams, predominates in Canada. Other derivative varieties include arena football, football for smaller teams, flag football and amateur games such as touch and street football. Football is played at professional, collegiate, high school, semi-professional, and amateur levels.
A down is a period in which a play transpires in gridiron football. The down is a distinguishing characteristic of the game compared to other codes of football, but is synonymous with a "tackle" in rugby league. The team in possession of the football has a limited number of downs to advance ten yards or more towards their opponent's goal line. If they fail to advance that far, possession of the ball is turned over to the other team. In most situations, if a team reaches their final down they will punt to their opponent, which forces them to begin their drive from further down the field; if they are in range, they might instead attempt to score a field goal.
This is a glossary of terms used in Canadian football. The Glossary of American football article also covers many terms that are also used in the Canadian version of the game.
American and Canadian football are gridiron codes of football that are very similar; both have their origins in rugby football, but some key differences exist.
Strategy forms a major part of American football. Both teams plan many aspects of their plays (offense) and response to plays (defense), such as what formations they take, who they put on the field, and the roles and instructions each player are given. Throughout a game, each team adapts to the other's apparent strengths and weaknesses, trying various approaches to outmaneuver or overpower their opponent in order to win the game.
American football positions have slowly evolved over the history of the sport. From its origins in early rugby football to the modern game, the names and roles of various positions have changed greatly, some positions no longer exist, and others have been created to fill new roles.
A formation in football refers to the position players line up in before the start of a down. There are both offensive and defensive formations and there are many formations in both categories. Sometimes, formations are referred to as packages.
Center (C) is a position in gridiron football. The center is the innermost lineman of the offensive line on a football team's offense. The center is also the player who passes the ball between his legs to the quarterback at the start of each play.
In gridiron football, the long snapper is a center on special teams whose duty is to snap the football over a longer distance, typically around 15 yards during punts, and 7–8 yards during field goals and extra point attempts.
A trick play, also known as a gadget play, gimmick play or trickeration, is a play in gridiron football that uses deception and unorthodox tactics to fool the opposing team. A trick play is often risky, offering the potential for a large gain or a touchdown if it is successful, but with the chance of a significant loss of yards or a turnover if not. Trick plays are rarely used not only because of the riskiness, but also to maintain the element of surprise for when they are used.
In American football, the specific role that a player takes on the field is referred to as their "position". Under the modern rules of American football, both teams are allowed 11 players on the field at one time and have "unlimited free substitutions", meaning that they may change any number of players during any "dead ball" situation. This has resulted in the development of three task-specific "platoons" of players within any single team: the offense, the defense, and the so-called 'special teams'. Within these three separate "platoons", various positions exist depending on the jobs that the players are doing.
A comparison between American football and rugby league is possible because of their shared origins and similar game concepts. Rugby league is arguably the most similar sport to American football after Canadian football: both sports involve the concept of a limited number of downs/tackles and scoring touchdowns/tries takes clear precedence over goal-kicking.
In American football, a play is a close-to-the-ground plan of action or strategy used to move the ball down the field. A play begins at either the snap from the center or at kickoff. Most commonly, plays occur at the snap during a down. These plays range from basic to very intricate. Football players keep a record of these plays in a playbook.
In gridiron football, motion refers to the movement of an offensive player at the time of the snap.
The following terms are used in American football, both conventional and indoor. Some of these terms are also in use in Canadian football; for a list of terms unique to that code, see Glossary of Canadian football.