College football is gridiron football that is played by teams of amateur student-athletes at universities and colleges. It was through collegiate competition that gridiron football first gained popularity in the United States.
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.
A free kick is an action used in several codes of football to restart play with the kicking of a ball into the field of play.
Gridiron football, also known as North American football, or in North America as simply football, is a family of football team sports primarily played in the United States and Canada. American football, which uses 11 players, is the form played in the United States and the best known form of gridiron football worldwide, while Canadian football, which uses 12 players, predominates in Canada. Other derivative varieties include arena football, flag football and amateur games such as touch and street football. Football is played at professional, collegiate, high school, semi-professional, and amateur levels.
Overtime or extra time is an additional period of play specified under the rules of a sport to bring a game to a decision and avoid declaring the match a tie or draw where the scores are the same. In some sports, this extra period is played only if the game is required to have a clear winner, as in single-elimination tournaments where only one team or players can advance to the next round or win the tournament and replays are not allowed.
A fair catch is a feature of American football and several other codes of football, in which a player attempting to catch a ball kicked by the opposing team – either on a kickoff or punt – is entitled to catch the ball without interference from any member of the kicking team. A player, usually a return specialist, wishing to make a fair catch signals his intent by extending one arm above his head and waving it while the kicked ball is in flight. A ball caught in this manner becomes dead once caught, i.e., the player catching the ball is not entitled to advance the ball, and the receiving team begins its drive at the spot where the ball was caught.
In American football, a touchback is a ruling that is made and signaled by an official when the ball becomes dead on or behind a team's own goal line and the opposing team gave the ball the momentum, or impetus, to travel over the goal line, but did not have possession of the ball when it became dead. Since the 2018 season, touchbacks have also been awarded in college football on kickoffs that end in a fair catch by the receiving team between its own 25-yard line and goal line. In the 2023 season, the NFL adopted the same rules as college football in regard to awarding touchbacks on kickoffs that end in a fair catch. In 2024, the NFL moved the placement of the ball after a touchback on a kickoff to the receiving team's 30-yard line; this was part of a radical change to the league's kickoff procedure. Such impetus may be imparted by a kick, pass, fumble, or in certain instances by batting the ball. A touchback is not a play, but a result of events that may occur during a play. A touchback is the opposite of a safety with regard to impetus since a safety is scored when the ball becomes dead in a team's end zone after that team — the team whose end zone it is — caused the ball to cross the goal line.
American and Canadian football are gridiron codes of football that are very similar; both have their origins partly in rugby football, but some key differences exist between the two codes.
Gameplay in American football consists of a series of downs, individual plays of short duration, outside of which the ball is or is 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 an aspect of game strategy that focuses on the game clock and/or play clock to achieve a desired result, typically near the end of a match. Depending on the game situation, clock management may entail playing in a manner that either slows or quickens the time elapsed from the game clock, to either extend the match or hasten its end. When the desired outcome is to end the match quicker, it is analogous to "running out the clock" seen in many sports. 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. Additionally, it may refer to a kickoff time, the scheduled time of the first kickoff of a game. 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, scores a touchdown, or the play is otherwise ruled dead. Kickoffs take place at the start of each half of play, the beginning of overtime in some overtime formats, and after scoring plays.
In gridiron football, the safety or safety touch is a scoring play that results in two points being awarded to the scoring team. Safeties can be scored in a number of ways, such as when a ball carrier is tackled in his own end zone or when a foul is committed by the offense in its own end zone. After a safety is scored in American football, the ball is kicked off to the team that scored the safety from the 20-yard line; in Canadian football, the scoring team also has the options of taking control of the ball at its own 35-yard line or kicking off the ball, also at its own 35-yard line. The ability of the scoring team to receive the ball through a kickoff differs from the touchdown and field goal, which require the scoring team to kick the ball off to the scored-upon team. Despite being of relatively low point value, safeties can have a significant impact on the result of games, and Brian Burke of Advanced NFL Stats estimated that safeties have a greater abstract value than field goals, despite being worth a point less, due to the field position and reclaimed possession gained off the safety kick.
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American football, referred to simply as football in the United States and Canada and also known as gridiron football, 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 throwing 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 the ball 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 the game wins.
In gridiron football, a penalty is a sanction assessed against a team for a violation of the rules, called a foul. Officials initially signal penalties by tossing a bright yellow colored penalty flag onto the field toward or at the spot of a foul.
In gridiron football, replay review is a method of reviewing a play using cameras at various angles to determine the accuracy of the initial call of the officials. An instant replay can take place in the event of a close or otherwise controversial call, either at the request of a team's head coach or the officials themselves.
In gridiron football, a two-point conversion, two-point convert, or two-point attempt 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 in addition to the six points for the touchdown, for a total of eight points. If the team fails, no additional points are scored.
The conversion, try, also known as a point(s) after touchdown, PAT, extra point, two-point conversion, or convert is a gridiron football play that occurs immediately after a touchdown. The scoring team attempts to score one extra point by kicking the ball through the uprights in the manner of a field goal, or two points by passing or running the ball into the end zone in the manner of a touchdown.
Helmet-to-helmet collisions are occurrences in gridiron football when two players' football helmets make head-to-head contact with a high degree of force. Intentionally causing a helmet-to-helmet collision is a penalty in most football leagues, including many high school leagues.
