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 indoor football and Arena football, football for smaller teams (most commonly eight players), and informal games such as touch and flag football. Football is played at professional, collegiate, high school, semi-professional, and amateur levels.
These sports originated in the 19th century out of older games related to modern rugby football, more specifically rugby union football. American and Canadian football developed alongside (but independently from) each other and were originally more distinct before Canadian teams adopted features of the American game.Both varieties are distinguished from other football sports by their use of hard plastic helmets and shoulder pads, the forward pass, the system of downs, a number of unique rules and positions, measurement in customary units of yards (even in Canada, which mostly metricated in the 1970s, yards are still used), and a distinctive brown leather ball in the shape of a prolate spheroid with pointed ends.
The international governing body for the sport is the International Federation of American Football (IFAF); although the organization plays all of its international competitions under American rules, it uses a definition of the game that is broad enough that it includes Canadian football under its umbrella, and Football Canada (the governing body for Canadian football) is an IFAF member.
The sport is typically known as simply "football" in the countries where it originated, regardless of the specific variety.Various sources use the term "North American football" when discussing the American and Canadian games together; however, this particular term is quite rare. It is also sometimes known as "gridiron football."
The American football and Canadian football fields originally resembled a cross-hatched gridiron, which influenced the term "gridiron football." This name originated with the sport's once-characteristic playing field, which produced a checkerboard effect.The original playing field was marked by a series of parallel lines along both the width and length of the field in a pattern resembling a cooking gridiron. The ball would be snapped in the grid in which it was downed on the previous play. By 1920, the grid system was abandoned in favor of the system of yard lines and hash marks used today (and still called a gridiron; the pattern changed, the name did not).
However, "gridiron football", or "gridiron", usually refers to American football specifically,sometimes in distinction from Canadian football. "Gridiron" is the usual name for American football in Australia and New Zealand. Some sources, including the International Federation of American Football (IFAF), use "American football" inclusive of Canadian football and other varieties.
The sport developed from informal games played in North America during the 19th century. Early games had a variety of local rules and were generally similar to modern rugby union and soccer. By the 1860s, teams from universities were playing each other, leading to more standardized rules and the creation of college football. While several American schools adopted rules based on the soccer rules of the English Football Association, Harvard University held to its traditional "carrying game". Meanwhile, McGill University in Montreal used rules based on rugby union. In 1874, Harvard and McGill organized two games using each other's rules. Harvard took a liking to McGill's rugby-style rules, and subsequently played several other U.S. colleges over the next several years using these rules.
American football teams and organizations subsequently adopted new rules which distinguished the game from rugby. 110-yard (100 m) field, 12-player teams, and three downs instead of four. Around the same time Camp devised the rules for American football, the Canadian game would develop in the same way (but separately) from the American game; the Burnside rules were instrumental in establishing many of the rules for the modern game.Many of these early innovations were the work of Walter Camp, including the sport's line of scrimmage and the system of a down. Another consequential change was the adoption of the forward pass in 1906, which allowed the quarterback to throw the ball forward over the line of scrimmage to a receiver. Canadian football remained akin to rugby for decades, though a progressive faction of players, chiefly based in the western provinces, demanded changes to the game based on the innovations in American football. Over the years, the sport adopted more Americanized rules, though it retained some of its historical features, including a
|National Football League||United States||American football||1920||32||$14.0||67,604||$2,700,000|
|Canadian Football League||Canada||Canadian football||1958||9||$0.2||27,005||$65,000|
|Indoor Football League||United States||Indoor football||2008||14||$3,500|
|Champions Indoor Football||United States||Indoor football||2014||7||$1,050|
|American Arena League||United States||Indoor football||2017||14|
|National Arena League||United States||Indoor football||2016||9||$2,450|
|Liga de Fútbol Americano Profesional||Mexico||American football||2016||8||2,000||$600|
|China Arena Football League||China||Arena football||2012||6||$7,500|
|X-League (X1/X2/X3)||Japan||American football||1971||18/18/17||$55,000|
The best NFL players are among the highest paid athletes in the world.
|NCAA||United States & Canada||American football||1906||4||673||No||27,142(Div. I)|
|NAIA||United States||American football||1940||1||94||No|
|NJCAA||United States||American football||1938||1||57||No|
|CCCAA||United States||American football||1929||1||68||No|
|U Sports||Canada||Canadian football||1961||1||27||No||3,370|
|KAFA||South Korea||American football||1945||1||39||No|
|BUAFL||United Kingdom||American football||2007||3||83||Yes|
|CSFL||United States||Sprint football||1940||1||10||No|
|NCFA||United States||American football||1940||1||27||No|
|100||10||531⁄3||11||7||4||10||No||At back of end zones|
181⁄2 (NFL and College) to 231⁄3 (High School) ft. wide
|110||20||65||12||7||3||10||Yes||On goal lines|
181⁄2 ft. wide
|Indoor||Spring||50||8||281⁄3||8||4||4||10||Yes||At back of end zones, 9 to 10 ft. wide|
Rebound nets on sides optional
|6-man||Fall||80||10||40||6||3||4||15||No||At back of end zones|
This is a minimal description of the game in general, with elements common to all or almost all variants of the game. For more specific rules, see each code's individual articles.
Prior to the start of a game, a coin toss determines which team will kick off the ball to their opponent. Each team lines up on opposite halves of the field, with a minimum ten yards of space between them for the kickoff. The team receiving the ball can make a fair catch (which stops the play immediately), catch the ball and run it back until the ball carrier is tackled, or, if the ball is kicked out of bounds, let the ball go dead on its own (the last case usually happens when the ball is kicked all the way into or through the opponent's end zone, resulting in a touchback and the ball being brought several yards out of the end zone to begin play). A kicking team can, under special circumstances, attempt to recover its own kick, but the rules of the game make it very difficult to do so reliably, and so this tactic is usually only used as a surprise or desperation maneuver.
At this point, play from scrimmage begins. The team in possession of the ball is on offense and the opponent is on defense. The offense is given a set amount of time (up to forty seconds, depending on the governing body), during which the teams can set up a play in a huddle and freely substitute players to set into a formation, in which the offense must remain perfectly still for at least one second (the formation requirement does not apply to Canadian football). At least half of the players (seven in standard American and Canadian football, four in standard indoor ball) on the offense must line up on the line of scrimmage in this formation, including the snapper, who handles the ball before play commences; the rest can (and almost always do) line up behind the line. Neither the offense nor the defense can cross the line of scrimmage before the play commences. Once the formation is set, the snapper snaps the ball to one of the players behind him. (A snapper must snap the ball within 20 to 25 seconds of the official setting the ball back into position after the previous play, and a play clock is kept to enforce the measure.) Once the ball is snapped, the play has commenced, and the offense's goal is to continue advancing the ball toward their opponent's end zone. This can be done either by running with the ball or by a rule unique to football known as the forward pass . In a forward pass, a player from behind the line of scrimmage throws the ball to an eligible receiver (another back or one player on each end of the line), who must catch the ball before it touches the ground. The play stops when a player with the ball touches any part of his body other than hand or foot to the ground, runs out of the boundaries of the field, is obstructed from making further forward progress, or a forward pass hits the ground without being caught (in the last case, the ball returns to the spot it was snapped). To stop play, players on defense are allowed to tackle the ball carrier at any time the ball is in play, provided they do not grab the face mask of the helmet or make helmet-to-helmet contact when doing so. At any time, the player with the ball can attempt a backward, or lateral, pass to any other player in order to keep the ball in play; this is generally rare. Any player on defense can, at any time, attempt to intercept a forward pass in flight, at which point the team gains possession; they can also gain possession by recovering a fumble or stripping the ball away from the ball carrier (a "forced fumble"). A typical play can last between five and twenty seconds.
In the event that any illegal action happens during the play, the results of the previous play are erased and a penalty is assessed, forcing the offending team to surrender between five and fifteen yards of field to the opponent. Whether this yardage is measured from the original spot of the ball before the play, the spot of the illegal action, or the end of the play depends on the individual foul. The most common penalties include false start (when an offensive player jumps to begin the play before the ball is snapped, a five-yard penalty), holding (the grabbing of a player other than the ball carrier to obstruct their progress; a ten-yard penalty against offensive players and a five-yard penalty against defensive ones), and pass interference (when either a receiver or the defending player pushes or blocks the other to prevent them from catching the pass). A team on offense cannot score points as the direct result of a penalty; a defensive foul committed in the team's own end zone, if the penalty is assessed from the spot of the foul, places the ball at the one-yard line. In contrast, a defensive team can score points as a direct result of a penalty; if the offense commits a foul under the same scenario, the defensive team receives two points and a free kick. In all other circumstances (except for the open-ended and extremely rare unfair act clause), a penalty cannot exceed more than half the distance to the end zone. In the event that the penalty would be less advantageous than the result of the actual play, the team not committing the penalty can decline it.
In order to keep play moving, the offense must make a certain amount of progress (10 yards in most leagues) within a certain number of plays (3 in Canada, 4 in the United States), called downs. If the offense does indeed make this progress, a first down is achieved, and the team gets 3 or 4 more plays to achieve another 10 yards. If not, the offense loses possession to their opponent at the spot where the ball is. More commonly, however, the team on offense will, if they have a minimal chance of gaining a first down and have only one play left to do it (fourth down in the U.S., third down in Canada), attempt a scrimmage kick. There are two types of scrimmage kick: a punt is when the ball is released from the punter's hand and kicked downfield as close to the opponent's end zone as possible without entering it; the kicking team loses possession of the ball after the kick and the receiving team can attempt to advance the ball or call a fair catch. The other scrimmage kick is a field goal attempt. This must be attempted by place kick or (more rarely) drop kick, and if the kicked ball passes through the goal set at the edge of the opponent's end zone, the team scores three points. (Four-point field goals have been offered in a few variations of the game under special rules, but the NFL, college and high school football only offer three-point field goals.) In Canada, any kick that goes into the end zone and is not returned, whether it be a punt or a missed field goal, is awarded one single point.
If the team in possession of the ball, at any time, advances (either by carrying or catching) the ball into the opponent's end zone, it is a touchdown, and the team scores six points and a free play known as a try. In a try, a team attempts to score one or two points (rules vary by each league, but under standard rules, a field goal on a try is worth one point while another touchdown is worth two). At the college and professional levels, the defense can also score on a try, but only on the same scale (thus a botched try the defense returns for a touchdown scores only two points and not six). Kickoffs occur after every touchdown and field goal.
If a team is in its own end zone and commits a foul, is tackled with the ball, or bats, fumbles, kicks or throws the ball backward out of the field of play through the same end zone, the defense scores a safety, worth two points.
After a try, safety or field goal, the team that had possession of the ball goes back to the middle of the field and kicks the ball off to their opponent, and play continues as it did in the beginning of the game.
Play continues until halftime. (Each team switches their side of the field with the other halfway through each half, at the end of a quarter.) After the halftime break, a new kickoff occurs. Whichever team has more points at the end of the game is declared the winner; in the event of a tie, each league has its own rules for overtime to break the tie. Because of the nature of the game, pure sudden-death overtimes have been abolished at all levels of the game as of 2012.
At all adult levels of the game, a game is 60 timed minutes in length, split into four 15-minute quarters. (High school football uses 12-minute quarters, and the general rule is that the younger the players, the shorter the quarters typically are.) Because of the halftime, quarter breaks, time-outs, the minute warnings (two minutes before the end of a half in the NFL, three minutes in Canadian football), and frequent stoppages of the game clock (the clock stops, for example, after every incomplete pass and any time a ball goes out of bounds), the actual time it takes for a football game to be completed is typically over three hours in the NFLand slightly under three hours in the CFL.
According to 2017 study on brains of deceased gridiron football players, 99% of tested brains of NFL players, 88% of CFL players, 64% of semi-professional players, 91% of college football players, and 21% of high school football players had various stages of CTE.
Other common injuries include, injuries of legs, arms and lower back.
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.
A snap is the backwards passing of the ball in gridiron football at the start of play from scrimmage.
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 a 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. The game is usually played by amateurs on a recreational basis.
A touchdown is a scoring play in gridiron football. Whether running, passing, returning a kickoff or punt, or recovering a turnover, a team scores a touchdown by advancing the ball into the opponent's end zone.
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.
Gameplay in American football consists of a series of downs, individual plays of short duration, outside of which the ball is dead or not in play. These can be plays from scrimmage – passes, runs, punts, or field goal attempts – or free kicks such as kickoffs and fair catch kicks. Substitutions can be made between downs, which allows for a great deal of specialization as coaches choose the players best suited for each particular situation. During a play, each team should have no more than 11 players on the field, and each of them has specific tasks assigned for that specific play.
In gridiron football, clock management is the manipulation of a game clock and play clock to achieve a desired result, typically near the end of a match. It is analogous to "running out the clock" seen in many sports, and the act of trying to hasten the game's end is often referred to by this term. Clock management strategies are a significant part of American football, where an elaborate set of rules dictates when the game clock stops between downs, and when it continues to run.
A kickoff is a method of starting a drive in gridiron football. Typically, a kickoff consists of one team – the "kicking team" – kicking the ball to the opposing team – the "receiving team". The receiving team is then entitled to return the ball, i.e., attempt to advance it towards the kicking team's end zone, until the player with the ball is tackled by the kicking team, goes out of bounds, or scores a touchdown. Kickoffs take place at the start of each half of play, the beginning of overtime in some overtime formats, and after scoring plays.
A comparison of American football and rugby union is possible because of the games' shared origins, despite their dissimilarities.
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.
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.
American football, referred to simply as football in the United States and Canada and also known as gridiron, is a team sport played by two teams of eleven players on a rectangular field with goalposts at each end. The offense, the team with possession of the oval-shaped football, attempts to advance down the field by running with the ball or passing it, while the defense, the team without possession of the ball, aims to stop the offense's advance and to take control of the ball for themselves. The offense must advance at least ten yards in four downs or plays; if they fail, they turn over the football to the defense, but if they succeed, they are given a new set of four downs to continue the drive. Points are scored primarily by advancing the ball into the opposing team's end zone for a touchdown or kicking the ball through the opponent's goalposts for a field goal. The team with the most points at the end of a game wins.
In gridiron football, a penalty is a sanction called against a team for a violation of the rules, called a foul. Officials initially signal penalties by tossing a bright yellow or orange colored penalty flag onto the field toward or at the spot of a foul. Many penalties result in moving the football toward the offending team's end zone, usually either 5, 10, or 15 yards, depending on the penalty. Most penalties against the defensive team also result in giving the offense an automatic first down, while a few penalties against the offensive team cause them to automatically lose a down. In some cases, depending on the spot of the foul, the ball is moved half the distance to the goal line rather than the usual number of yards, or the defense scores an automatic safety.
In gridiron football, a two-point conversion or two-point convert is a play a team attempts instead of kicking a one-point conversion immediately after it scores a touchdown. In a two-point conversion attempt, the team that just scored must run a play from scrimmage close to the opponent's goal line and advance the ball across the goal line in the same manner as if they were scoring a touchdown. If the team succeeds, it earns two additional points on top of the six points for the touchdown, for a total of eight points. If the team fails, no additional points are scored. In either case, if any time remains in the half, the team proceeds to a kickoff.
A comparison of Canadian football and rugby union is possible because of the games' shared origins, despite their dissimilarities.
In gridiron football, a punt is a kick performed by dropping the ball from the hands and then kicking the ball before it hits the ground. The most common use of this tactic is to punt the ball downfield to the opposing team, usually on the final down, with the hope of giving the receiving team a field position that is more advantageous to the kicking team when possession changes. The result of a typical punt, barring any penalties or extraordinary circumstances, is a first down for the receiving team. A punt is not to be confused with a drop kick, a kick after the ball hits the ground, now rare in both American and Canadian football.