American football (referred to simply as football in the United States and Canada), also known as gridiron, is a

team sport A team sport includes any sport where individuals are organized into opposing teams which compete to win or cooperate to entertain their audience. Team members act together towards a shared objective. This can be done in a number of ways s ...

played by two teams of eleven players on a rectangular

field Field may refer to: Expanses of open ground * Field (agriculture), an area of land used for agricultural purposes * Airfield, an aerodrome that lacks the infrastructure of an airport * Battlefield * Lawn, an area of mowed grass * Meadow, a grass ...

with goalposts at each end. The offense, the team with possession of the oval-shaped football, attempts to advance down the field by

running Running is a method of terrestrial locomotion allowing humans and other animals to move rapidly on foot. Running is a type of gait characterized by an aerial phase in which all feet are above the ground (though there are exceptions). This is ...

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 Drive or The Drive may refer to: Motoring * Driving, the act of controlling a vehicle * Road trip, a journey on roads Roadways Roadways called "drives" may include: * Driveway, a private road for local access to structures, abbreviated "drive" ...

. Points are scored primarily by advancing the ball into the opposing team's

end zone The end zone is the scoring area on the field, according to gridiron-based codes of football. It is the area between the end line and goal line bounded by the sidelines. There are two end zones, each being on an opposite side of the field. ...

for a

touchdown A touchdown (abbreviated as TD) 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. In Amer ...

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. American football evolved in the United States, originating from the sports of soccer and

rugby Rugby may refer to: Sport * Rugby football in many forms: ** Rugby league: 13 players per side *** Masters Rugby League *** Mod league *** Rugby league nines *** Rugby league sevens *** Touch (sport) *** Wheelchair rugby league ** Rugby union: 1 ...

. The first American football match was played on November 6, 1869, between two college teams,

Rutgers Rutgers University (; RU), officially Rutgers, The State University of New Jersey, is a public land-grant research university consisting of four campuses in New Jersey. Chartered in 1766, Rutgers was originally called Queen's College, and w ...

and

Princeton Princeton University is a private research university in Princeton, New Jersey. Founded in 1746 in Elizabeth as the College of New Jersey, Princeton is the fourth-oldest institution of higher education in the United States and one of the ni ...

, using rules based on the rules of soccer at the time. A set of rule changes drawn up from 1880 onward by

Walter Camp Walter Chauncey Camp (April 7, 1859 – March 14, 1925) was an American football player, coach, and sports writer known as the "Father of American Football". Among a long list of inventions, he created the sport's line of scrimmage and the system ...

, the "Father of American Football", established the

snap Snap or SNAP may refer to: Arts and entertainment * ''Snap'', the original release title for the 2013 film ''Enter the Dangerous Mind'' *''Snap'' (TV series), a CITV programme * ''The Stanly News and Press'', a newspaper in Albemarle, North Carol ...

, the

line of scrimmage In gridiron football, a line of scrimmage is an imaginary transverse line (across the width of the field) 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 o ...

, eleven-player teams, and the concept of downs. Later rule changes legalized the

forward pass In several forms of football, a forward pass is the throwing of the ball in the direction in which the offensive team is trying to move, towards the defensive team's goal line. The forward pass is one of the main distinguishers between gridir ...

, created the neutral zone and specified the size and shape of the football. The sport is closely related to

Canadian football 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 long and wide attempting to advance a pointed oval-shaped ball into the opposing team's scoring area ( ...

, which evolved in parallel with and at the same time as the American game, although its rules were developed independently from those of Camp. Most of the features that distinguish American football from rugby and soccer are also present in Canadian football. The two sports are considered the primary variants of gridiron football. American football is the most popular sport in the United States in terms of broadcast viewership audience. The most popular forms of the game are

professional A professional is a member of a profession or any person who works in a specified professional activity. The term also describes the standards of education and training that prepare members of the profession with the particular knowledge and ski ...

and college football, with the other major levels being

high-school A secondary school describes an institution that provides secondary education and also usually includes the building where this takes place. Some secondary schools provide both '' lower secondary education'' (ages 11 to 14) and ''upper seconda ...

and youth football. , nearly 1.1 million high-school athletes and 70,000 college athletes play the sport in the United States annually. The

National Football League The National Football League (NFL) is a professional American football league that consists of 32 teams, divided equally between the American Football Conference (AFC) and the National Football Conference (NFC). The NFL is one of the ...

, the most popular American professional football league, has the highest average attendance of any professional sports league in the world. Its championship game, the Super Bowl, ranks among the most-watched club sporting events in the world. The league has an annual revenue of around US$15 billion, making it the most valuable sports league in the world. Other professional leagues exist worldwide, but the sport does not have the international popularity of other American sports like

baseball Baseball is a bat-and-ball sport played between two teams of nine players each, taking turns batting and fielding. The game occurs over the course of several plays, with each play generally beginning when a player on the fielding t ...

basketball Basketball is a team sport in which two teams, most commonly of five players each, opposing one another on a rectangular court, compete with the primary objective of shooting a basketball (approximately in diameter) through the defender's h ...

Etymology and names

In the United States, American football is referred to as "football". The term "football" was officially established in the rulebook for the 1876 college football season, when the sport first shifted from soccer-style rules to rugby-style rules. Although it could easily have been called "rugby" at this point, Harvard, one of the primary proponents of the rugby-style game, compromised and did not request the name of the sport be changed to "rugby". The terms " gridiron" or "American football" are favored in English-speaking countries where other types of football are popular, such as the United Kingdom, Ireland, New Zealand, and Australia.

History

Early history

American football evolved from the sports of

and soccer. Rugby, like American football, is a sport where two competing teams vie for control of a ball, which can be kicked through a set of goalposts or run into the opponent's goal area to score points. What is considered to be the first American football game was played on November 6, 1869, between

and

, two college teams. They consisted of 25 players per team and used a round ball that could not be picked up or carried. It could, however, be kicked or batted with the feet, hands, head or sides, with the objective being to advance it into the opponent's goal. Rutgers won the game 6–4. Collegiate play continued for several years with matches played using the rules of the host school. Representatives of Yale, Columbia, Princeton and Rutgers met on October 19, 1873, to create a standard set of rules for use by all schools. Teams were set at 20 players each, and fields of were specified. Harvard abstained from the conference, as they favored a rugby-style game that allowed running with the ball. After playing

McGill University McGill University (french: link=no, Université McGill) is an English-language public research university located in Montreal, Quebec Montreal ( ; officially Montréal, ) is the second-most populous city in Canada and most populous ...

using both Canadian and American rules, the Harvard players preferred the Canadian style of having only 11 men on the field, running the ball without having to be chased by an opponent, the forward pass, tackling, and using an oblong instead of a round ball. An 1875 Harvard–Yale game played under rugby-style rules was observed by two Princeton athletes who were impressed by it. They introduced the sport to Princeton, a feat the Professional Football Researchers Association compared to "selling refrigerators to Eskimos". Princeton, Harvard, Yale, and Columbia then agreed to intercollegiate play using a form of

rugby union Rugby union, commonly known simply as rugby, is a close-contact team sport that originated at Rugby School in the first half of the 19th century. One of the two codes of rugby football, it is based on running with the ball in hand. In it ...

rules with a modified scoring system. These schools formed the

Intercollegiate Football Association The Intercollegiate Football Association (IFA), also known as the American Intercollegiate Football Association, was one of the earliest college football rules-making and scheduling organizations in existence; it was active from the 1873 to 1893 ...

, although Yale did not join until 1879. Yale player

, now regarded as the "Father of American Football", secured rule changes in 1880 that reduced the size of each team from 15 to 11 players and instituted the

to replace the chaotic and inconsistent

scrum Scrum may refer to: Sport * Scrum (rugby), a method of restarting play in rugby union and rugby league ** Scrum (rugby union), scrum in rugby union * Scrum, an offensive melee formation in Japanese game Bo-taoshi Media and popular culture * M ...

. While the game between Rutgers and Princeton is commonly considered the first American football game, several years prior in 1862, the

Oneida Football Club The Oneida Football Club, founded and captained by Gerrit Smith Miller in Boston, Massachusetts, in 1862, was the first organized team to play any kind of football in the United States. The introduction of the snap resulted in an unexpected consequence. Before the snap, the strategy had been to punt if a scrum resulted in bad field position. However, a group of Princeton players realized that as the snap was uncontested, they could now hold the ball indefinitely to prevent their opponent from scoring. In 1881, in a game between Yale and Princeton, both teams used this strategy to maintain their undefeated records. Each team held the ball, gaining no ground, for an entire half, resulting in a 0–0 tie. This "block game" proved extremely unpopular with both teams' spectators and fans. A rule change was necessary to prevent this strategy from taking hold, and a reversion to the scrum was considered. However, Camp successfully proposed a rule in 1882 that limited each team to three downs, or tackles, to advance the ball . Failure to advance the ball the required distance within those three downs would result in control of the ball being forfeited to the other team. This change effectively made American football a separate sport from rugby, and the resulting five-yard lines added to the field to measure distances made it resemble a gridiron in appearance. Other major rule changes included a reduction of the field size to and the adoption of a scoring system that awarded four points for a touchdown, two for a safety and a goal following a touchdown, and five for a goal from the field. Additionally, tackling below the waist was legalized, and a static

was instituted. WCMorris Spokesman-Review cartoons 099 (1)

Despite these new rules, football remained a violent sport. Dangerous mass-formations like the

flying wedge A flying wedge (also called flying V or wedge formation, or simply wedge) is a configuration created from a body moving forward in a triangular formation. This V-shaped arrangement began as a successful military strategy in ancient times when inf ...

resulted in serious injuries and deaths. A 1905 peak of 19 fatalities nationwide resulted in a threat by President

Theodore Roosevelt Theodore Roosevelt Jr. ( ; October 27, 1858 – January 6, 1919), often referred to as Teddy or by his initials, T. R., was an American politician, statesman, soldier, conservationist, naturalist, historian, and writer who served as the 26t ...

to abolish the game unless major changes were made. In response, 62 colleges and universities met in New York City to discuss rule changes on December 28, 1905. These proceedings resulted in the formation of the Intercollegiate Athletic Association of the United States, later renamed the

National Collegiate Athletic Association The National Collegiate Athletic Association (NCAA) is a nonprofit organization that regulates student athletics among about 1,100 schools in the United States, Canada, and Puerto Rico. It also organizes the athletic programs of colleges ...

(NCAA). The legal

was introduced in 1906, although its effect was initially minimal due to the restrictions placed on its use. The idea of a 40-yard-wider field was opposed by Harvard due to the size of the new

Harvard Stadium Harvard Stadium is a U-shaped college football stadium in the northeast United States, located in the Allston neighborhood of Boston, Massachusetts. The stadium is owned and operated by Harvard University and is home to the Harvard Crimson footb ...

. Other rule changes introduced that year included the reduction of playing time from 70 to 60 minutes and an increase of the distance required for a first down from . To reduce infighting and dirty play between teams, the neutral zone was created along the width of the football before the snap. Scoring was also adjusted: points awarded for field goals were reduced to three in 1909 and points for touchdowns were raised to six in 1912. Also in 1912, the field was shortened to long, two end zones were created, and teams were given four downs instead of three to advance the ball . The

roughing the passer In gridiron football, roughing the passer is a foul in which a defensive player makes illegal contact with the quarterback after the latter has thrown a forward pass. The penalty is 10 or 15 yards, depending on the league, and an automatic first d ...

penalty was implemented in 1914, and eligible players were first allowed to catch the ball anywhere on the field in 1918.

Professional era

Indiana Soldier's and Sailor's Home football team, 1896

On November 12, 1892,

Pudge Heffelfinger William Walter "Pudge" Heffelfinger (December 20, 1867 – April 2, 1954), also spelled Hafelfinger, was an American football player and coach. He is considered the first athlete to play American football professionally, having been paid to pl ...

was paid $500 () to play a game for the

Allegheny Athletic Association The Allegheny Athletic Association was an athletic club that fielded the first ever professional American football player and later the first fully professional football team. The organization was founded in 1890 as a regional athletic club in A ...

in a match against the

Pittsburgh Athletic Club The Pittsburgh Athletic Club (PAC) was one of the earliest professional ice hockey teams. It was based in Pittsburgh, Pennsylvania from around 1895 until 1904 and again from 1907 to 1909. The team was a member of the Western Pennsylvania Hockey Le ...

. This is the first recorded instance of a player being paid to participate in a game of American football, although many athletic clubs in the 1880s offered indirect benefits, such as helping players attain employment, giving out trophies or watches that players could pawn for money, or paying double in expense money. Despite these extra benefits, the game had a strict sense of amateurism at the time, and direct payment to players was frowned upon, if not prohibited outright. Over time, professional play became increasingly common, and with it came rising salaries and unpredictable player movement, as well as the illegal payment of college players who were still in school. The

(NFL), a group of professional teams that was originally established in 1920 as the American Professional Football Association, aimed to solve these problems. This new league's stated goals included an end to bidding wars over players, prevention of the use of college players, and abolition of the practice of paying players to leave another team. By 1922, the NFL had established itself as America's premier professional football league. The dominant form of football at the time was played at the collegiate level. The upstart NFL received a boost to its legitimacy in 1925, however, when an NFL team, the

Pottsville Maroons The Pottsville Maroons were an American football team based in Pottsville, Pennsylvania, in the northeastern part of the state. Founded in 1920, they played in the National Football League (NFL) from 1925 to 1928. In 1929 they relocated to Bosto ...

, defeated a team of Notre Dame all-stars in an exhibition game. A greater emphasis on the passing game helped professional football to distinguish itself further from the college game during the late 1930s. Football, in general, became increasingly popular following the 1958 NFL Championship game, a match between the Baltimore Colts and the New York Giants that is still referred to as the "Greatest Game Ever Played". The game, a 23–17 overtime victory by the Colts, was seen by millions of television viewers and had a major influence on the popularity of the sport. This, along with the innovations introduced by the new American Football League (AFL) in the early 1960s, helped football to become the most popular sport in the United States by the mid-1960s. The rival AFL arose in 1960 and challenged the NFL's dominance. The AFL began in relative obscurity but eventually thrived, with an initial television contract with the

ABC ABC are the first three letters of the Latin script known as the alphabet. ABC or abc may also refer to: Arts, entertainment, and media Broadcasting * American Broadcasting Company, a commercial U.S. TV broadcaster ** Disney–ABC Television ...

television network. The AFL's existence forced the conservative NFL to expand to Dallas and Minnesota in an attempt to destroy the new league. Meanwhile, the AFL introduced many new features to professional football in the United States: official time was kept on a scoreboard clock rather than on a watch in the referee's pocket, as the NFL did; optional two-point conversions by pass or run after touchdowns; names on the jerseys of players; and several others, including expansion of the role of minority players, actively recruited by the league in contrast to the NFL. The AFL also signed several star college players who had also been drafted by NFL teams. Competition for players heated up in 1965, when the AFL New York Jets signed rookie Joe Namath to a then-record $437,000 contract (equivalent to $ in ). A five-year, $40 million

NBC The National Broadcasting Company (NBC) is an American English-language commercial broadcast television and radio network. The flagship property of the NBC Entertainment division of NBCUniversal, a division of Comcast, its headquarters are l ...

television contract followed, which helped to sustain the young league. The bidding war for players ended in 1966 when NFL owners approached the AFL regarding a merger, and the two leagues agreed on one that took full effect in 1970. This agreement provided for a common draft that would take place each year, and it instituted an annual World Championship game to be played between the champions of each league. This championship game began play at the end of the 1966 season. Once the merger was completed, it was no longer a championship game between two leagues and reverted to the NFL championship game, which came to be known as the Super Bowl. College football maintained a tradition of postseason

bowl games In North America, a bowl game is one of a number of post-season college football games that are primarily played by teams belonging to the National Collegiate Athletic Association, NCAA's NCAA Division I Football Bowl Subdivision, Division I Fo ...

. Each bowl game was associated with a particular conference and earning a spot in a bowl game was the reward for winning a conference. This arrangement was profitable, but it tended to prevent the two top-ranked teams from meeting in a true national championship game, as they would normally be committed to the bowl games of their respective conferences. Several systems have been used since 1992 to determine a national champion of college football. The first was the

Bowl Coalition The College Football Bowl Coalition was formed through an agreement among Division I-A college football bowl games and conferences for the purpose of forcing a national championship game between the top two teams and to provide quality bowl game ...

, in place from 1992 to 1994. This was replaced in 1995 by the

Bowl Alliance The Bowl Alliance was an agreement among college football bowl games (specifically the Sugar, Orange, and Fiesta Bowls) for the purpose of trying to match the top two teams in a national championship game and to provide quality bowl game match ...

, which gave way in 1997 to the Bowl Championship Series (BCS). The BCS arrangement proved to be controversial, and was replaced in 2014 by the

College Football Playoff The College Football Playoff (CFP) is an annual postseason knockout invitational tournament to determine a national champion for the National Collegiate Athletic Association (NCAA) Division I Football Bowl Subdivision (FBS), the highest level ...

(CFP).

Teams and positions

A football game is played between two teams of 11 players each.NFL Rules 2012, p. 21.NFHS Rules 2012, p. 11. Playing with more on the field is punishable by a penalty.NCAA Rules 2011–2012, p. 107.NFHS Rules 2012, pp. 71–72. Teams may substitute any number of their players between downs;NFL Rules 2012, pp. 21–22.NCAA Rules 2011–2012, pp. 53–54.NFHS Rules 2012, pp. 45–46. this "platoon" system replaced the original system, which featured limited substitution rules, and has resulted in teams utilizing specialized offensive, defensive and

special teams 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 substitu ...

units. Individual players in a football game must be designated with a

uniform number In team sports, the number, often referred to as the uniform number, squad number, jersey number, shirt number, sweater number, or similar (with such naming differences varying by sport and region) is the number worn on a player's uniform, to ...

between 1 and 99. NFL teams are required to number their players by a league-approved numbering system, and any exceptions must be approved by the commissioner. NCAA and NFHS teams are "strongly advised" to number their offensive players according to a league-suggested numbering scheme.NCAA Rules 2011–2012, pp. 21–22.NFHS Rules 2012, pp. 16–17. Although the sport is played almost exclusively by men, women are eligible to play in high school, college, and professional football. No woman has ever played in the NFL, but women have played in high school and college football games. In 2018, 1,100 of the 225,000 players in

Pop Warner Little Scholars Pop Warner Little Scholars, commonly known simply as Pop Warner, is a nonprofit organization that provides activities such as American football, for over 425,000 youths aged 5 to 16 years old, in several nations. It is the largest youth footbal ...

youth football were girls, and around 11% of the 5.5 million Americans who report playing tackle football are female according to the Sports and Fitness Industry Association. Women can also serve as officials; Sarah Thomas became the NFL's first female official in 2015.

Offensive unit

The role of the offensive unit is to advance the football down the field with the ultimate goal of scoring a

The offensive team must line up in a legal

formation Formation may refer to: Linguistics * Back-formation, the process of creating a new lexeme by removing or affixes * Word formation, the creation of a new word by adding affixes Mathematics and science * Cave formation or speleothem, a secondar ...

before they can snap the ball. An offensive formation is considered illegal if there are more than four players in the

backfield The offensive backfield is the area of an American football field behind the line of scrimmage. The offensive backfield can also refer to members of offense who begin plays behind the line, typically including any backs on the field, such as the ...

or fewer than five players numbered 50–79 on the offensive line.NCAA Rules 2011–2012, p. 15.NFL Rules 2012, pp. 21–24.NFHS Rules 2012, pp. 57–58. Players can line up temporarily in a position whose eligibility is different from what their number permits as long as they report the change immediately to the referee, who then informs the defensive team of the change.NFL Rules 2012, pp. 36, 40. Neither team's players, except the

center Center or centre may refer to: Mathematics *Center (geometry), the middle of an object * Center (algebra), used in various contexts ** Center (group theory) ** Center (ring theory) * Graph center, the set of all vertices of minimum eccentrici ...

(C), are allowed to line up in or cross the neutral zone until the ball is snapped. Interior offensive linemen are not allowed to move until the snap of the ball. Hurricanes Quarterback

The main backfield positions are the

quarterback The quarterback (commonly abbreviated "QB"), colloquially known as the "signal caller", is a position in gridiron football. Quarterbacks are members of the offensive platoon and mostly line up directly behind the offensive line. In modern Ame ...

(QB), halfback/tailback (HB/TB) and fullback (FB). The quarterback is the leader of the offense. Either the quarterback or a coach calls the plays. Quarterbacks typically inform the rest of the offense of the play in the

huddle In sport, a huddle is the action of a team gathering together, usually in a tight circle, to strategize, motivate or celebrate. It is a popular strategy for keeping opponents insulated from sensitive information, and acts as a form of insulation ...

before the team lines up. The quarterback lines up behind the center to take the snap and then hands the ball off, throws it or runs with it. The primary role of the halfback, also known as the

running back A running back (RB) is a member of the offensive backfield in gridiron football. The primary roles of a running back are to receive handoffs from the quarterback to rush the ball, to line up as a receiver to catch the ball, and block. Ther ...

or tailback, is to carry the ball on running plays. Halfbacks may also serve as receivers. Fullbacks tend to be larger than halfbacks and function primarily as blockers, but they are sometimes used as runners in short-yardage situations and are seldom used in passing situations. The

offensive line In gridiron football, a lineman is a player who specializes in play at the line of scrimmage. The linemen of the team currently in possession of the ball are the offensive line, while linemen on the opposing team are the defensive line. A numb ...

(OL) consists of several players whose primary function is to

block Block or blocked may refer to: Arts, entertainment and media Broadcasting * Block programming, the result of a programming strategy in broadcasting * W242BX, a radio station licensed to Greenville, South Carolina, United States known as ''96.3 ...

members of the defensive line from tackling the ball carrier on running plays or sacking the quarterback on passing plays. The leader of the offensive line is the center, who is responsible for snapping the ball to the quarterback, blocking, and for making sure that the other linemen do their jobs during the play. On either side of the center are the guards (G), while

tackles Tackle may refer to: * In football: ** Tackle (football move), a play in various forms of football ** Tackle (gridiron football position), a position in American football and Canadian football ** Dump tackle, a forceful move in rugby of picking u ...

(T) line up outside the guards. The principal receivers are the wide receivers (WR) and the

tight end The tight end (TE) is a position in American football, arena football, and Canadian football, on the offense. The tight end is often a hybrid position with the characteristics and roles of both an offensive lineman and a wide receiver. Lik ...

s (TE). Wide receivers line up on or near the line of scrimmage, split outside the line. The main goal of the wide receiver is to catch passes thrown by the quarterback, but they may also function as decoys or as blockers during running plays. Tight ends line up outside the tackles and function both as receivers and as blockers.

Defensive unit

The role of the defense is to prevent the offense from scoring by

tackling Tackle may refer to: * In football: ** Tackle (football move), a play in various forms of football ** Tackle (gridiron football position), a position in American football and Canadian football ** Dump tackle, a forceful move in rugby of picking up ...

the ball carrier or by forcing turnovers (

interception In ball-playing competitive team sports, an interception or pick is a move by a player involving a pass of the ball—whether by foot or hand, depending on the rules of the sport—in which the ball is intended for a player of the same team ...

s or fumbles). The

defensive line In gridiron football, a lineman is a player who specializes in play at the line of scrimmage. The linemen of the team currently in possession of the ball are the offensive line, while linemen on the opposing team are the defensive line. A numb ...

(DL) consists of

defensive end Defensive end (DE) is a defensive position in the sport of gridiron football. This position has designated the players at each end of the defensive line, but changes in formations over the years have substantially changed how the position is ...

s (DE) and defensive tackles (DT). Defensive ends line up on the ends of the line, while defensive tackles line up inside, between the defensive ends. The primary responsibilities of defensive ends and defensive tackles are to stop running plays on the outside and inside, respectively, to pressure the quarterback on passing plays, and to occupy the line so that the

linebacker Linebacker (LB) is a playing position in gridiron football. Linebackers are members of the defensive team, and line up three to five yards behind the line of scrimmage and the defensive linemen. They are the "middle ground" of defenders, ...

s can break through. Brent Grimes-Hamburg Sea Devils

Linebackers line up behind the defensive line but in front of the defensive backfield. They are divided into two types: middle linebackers (MLB) and outside linebackers (OLB). Linebackers are the defensive leaders and call the defensive plays. Their diverse roles include defending the run, pressuring the quarterback, and guarding backs, wide receivers and tight ends in the passing game. The defensive backfield, often called the secondary, consists of

cornerback A cornerback (CB) is a member of the defensive backfield or secondary in gridiron football. Cornerbacks cover Wide receiver, receivers most of the time, but also blitz and defend against such Play from scrimmage, offensive running plays as sweep ...

s (CB) and

safeties Safety is the condition of being protected against harmful conditions or events, or the control of hazards to reduce risk. Safety may also refer to: Places * Safety Island, Antarctica Government * The Internet Stopping Adults Facilitating t ...

(S). Safeties are themselves divided into free safeties (FS) and strong safeties (SS). Cornerbacks line up outside the defensive formation, typically opposite a receiver to be able to cover them. Safeties line up between the cornerbacks but farther back in the secondary. Safeties are the last line of defense and are responsible for stopping deep passing plays as well as running plays.

Special teams unit

The special teams unit is responsible for all kicking plays. The special teams unit of the team in control of the ball tries to execute field goal (FG) attempts, punts and kickoffs, while the opposing team's unit will aim to block or return them. Three positions are specific to the field goal and PAT (point-after-touchdown) unit: the placekicker (K or PK), holder (H) and

long snapper In American football, the long snapper (or deep 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 att ...

(LS). The long snapper's job is to snap the football to the holder, who will catch and position it for the placekicker. There is not usually a holder on kickoffs, because the ball is kicked off a tee; however, a holder may be used in certain situations, such as if wind is preventing the ball from remaining upright on the tee. The player on the receiving team who catches the ball is known as the

kickoff returner A return specialist or kick returner is a player on the special teams unit of a gridiron football team who specializes in returning punts and kickoffs. There are few players who are exclusively return specialists; most also play another positio ...

(KR). The positions specific to punt plays are the punter (P), long snapper,

upback In American football, the upback (also known as the punt protector or personal protector) is a blocking back who lines up approximately 1–3 yards behind the line of scrimmage in punting situations. Because the punter plays so far back, the upba ...

and gunner. The long snapper snaps the football directly to the punter, who then drops and kicks it before it hits the ground. Gunners line up split outside the line and race down the field, aiming to tackle the punt returner (PR)—the player who catches the punt. Upbacks line up a short distance behind the line of scrimmage, providing additional protection to the punter.

Rules

Scoring

In football, the winner is the team that has scored more points at the end of the game. There are multiple ways to score in a football game. The touchdown (TD), worth six points, is the most valuable scoring play in American football. A touchdown is scored when a live ball is advanced into, caught in, or recovered in the opposing team's end zone. The scoring team then attempts a try or conversion, more commonly known as the point(s)-after-touchdown (PAT), which is a single scoring opportunity. A PAT is most commonly attempted from the two- or three-yard line, depending on the level of play. If a PAT is scored by a place kick or drop kick through the goal posts, it is worth one point, typically called the extra point. If it is scored by what would normally be a touchdown it is worth two points, typically called the

two-point conversion 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 ...

. In general, the extra point is almost always successful, while the two-point conversion is a much riskier play with a higher probability of failure; accordingly, extra point attempts are far more common than two-point conversion attempts. A field goal (FG), worth three points, is scored when the ball is place kicked or drop kicked through the uprights and over the crossbars of the defense's goalposts.NFL Rules 2012, pp. 57–59.NCAA Rules 2011–2012, pp. 79–80.NFHS Rules 2012, p. 66. After a PAT attempt or successful field goal, the scoring team must kick the ball off to the other team. A

safety Safety is the state of being "safe", the condition of being protected from harm or other danger. Safety can also refer to the control of recognized hazards in order to achieve an acceptable level of risk. Meanings There are two slightly dif ...

is scored when the ball carrier is tackled in his own end zone. Safeties are worth two points, which are awarded to the defense. In addition, the team that conceded the safety must kick the ball to the scoring team via a

free kick 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. Association football In association football, the free kick is a method of restarting the game following an offe ...

.NFL Rules 2012, p. 60

Field and equipment

Football games are played on a rectangular

that measures long and wide. Lines marked along the ends and sides of the field are known as the end lines and sidelines. Goal lines are marked inward from each end line.NFL Rules 2012, p. v, 1.NCAA Rules 2011–2012, pp. 18–19, 23–24.NFHS Rules 2012, pp. 11–12, 13, 28. Weighted pylons are placed the sidelines on the inside corner of the intersections with the goal lines and end lines. White markings on the field identify the distance from the end zone. Inbound lines, or

hash marks In sports, a hash mark or hash line is a short line/bar marking that is painted perpendicular to the sidelines or side barricades, used to help referees and players recognize on-field locations and visually measure distances. Hash marks serve the ...

, are short parallel lines that mark off increments.

Yard lines The rectangular field of play used for American football games measures long between the goal lines, and (53.3 yards) wide. The field may be made of grass or artificial turf. In addition, there are end zones extending another past the goal li ...

, which can run the width of the field, are marked every . A one-yard-wide line is placed at each end of the field; this line is marked at the center of the two-yard line in professional play and at the three-yard line in college play. Numerals that display the distance from the closest goal line in yards are placed on both sides of the field every ten yards.

Goalposts In sport, a goal may refer to either an instance of scoring, or to the physical structure or area where an attacking team must send the ball or puck in order to score points. The structure of a goal varies from sport to sport, and one is place ...

are located at the center of the plane of the two end lines. The crossbar of these posts is above the ground, with vertical uprights at the end of the crossbar apart for professional and collegiate play, and apart for high school play. The uprights extend vertically on professional fields, a minimum of on college fields, and a minimum of on high school fields. Goal posts are padded at the base, and orange ribbons are normally placed at the tip of each upright as indicators of wind strength and direction.NFL Rules 2012, p. 2.NCAA Rules 2011–2012, p. 18.NFHS Rules 2012, p. 14. The football itself is an oval ball, similar to the balls used in rugby or Australian rules football. At all levels of play, the football is inflated to and weighs ;NCAA Rules 2011–2012, p. 20.NFL Rules 2012, p. 3. beyond that, the exact dimensions vary slightly. In professional play the ball has a long axis of , a long circumference of , and a short circumference of . In college and high school play the ball has a long axis of , a long circumference of , and a short circumference of .

Duration and time stoppages

Football games last for a total of 60 minutes in professional and college play and are divided into two halves of 30 minutes and four quarters of 15 minutes.NFL Rules 2012, p. 14.NCAA Rules 2011–2012, p. 45. High school football games are 48 minutes in length with two halves of 24 minutes and four quarters of 12 minutes.NFHS Rules 2012, pp. 38–39. The two halves are separated by a

halftime In several team sports, matches are played in two halves. Half-time (also written halftime or half time) is the name given to the interval between the two halves of the match. Typically, after half-time, teams swap ends of the field of play in ...

period, and the first and third quarters are followed by a short break.NFHS Rules 2012, p. 39. Before the game starts, the referee and each team's captain meet at midfield for a

coin toss A coin is a small, flat (usually depending on the country or value), round piece of metal or plastic used primarily as a medium of exchange or legal tender. They are standardized in weight, and produced in large quantities at a mint in order to ...

. The visiting team can call either "heads" or "tails"; the winner of the toss chooses whether to receive or kick off the ball or which goal they wish to defend. They can defer their choice until the second half. Unless the winning team decides to defer, the losing team chooses the option the winning team did not select—to receive, kick, or select a goal to defend to begin the second half. Most teams choose to receive or defer, because choosing to kick the ball to start the game allows the other team to choose which goal to defend. Teams switch goals following the first and third quarters. If a down is in progress when a quarter ends, play continues until the down is completed.NFL Rules 2012, pp. 14–18NCAA Rules 2011–2012, pp. 47–53.NFHS Rules 2012, pp. 38–45 Games last longer than their defined length due to play stoppages—the average NFL game lasts slightly over three hours. Time in a football game is measured by the game clock. An operator is responsible for starting, stopping and operating the game clock based on the direction of the appropriate official.NCAA Rules 2011–2012, pp. 16, 41. A separate

play clock A play clock, also called a delay-of-game timer, is a countdown clock intended to speed up the pace of the game in gridiron football. The offensive team must put the ball in play by either snapping the ball during a scrimmage down or kicking the ...

is used to show the amount of time within which the offense must initiate a play. The play clock is set to 25 seconds after certain administrative stoppages in play and to 40 seconds when play is proceeding without such stoppages. If the offense fails to start a play before the play clock reads "00", a

delay of game Delay of game is an action in a sports game in which a player or team deliberately stalls the game, usually with the intention of using the delay to its advantage. In some sports, the delay of game is considered an infraction if it is longer than ...

foul is called on the offense.NCAA Rules 2011–2012, pp. 41, 46–47.NFHS Rules 2019.

Advancing the ball and downs

There are two main ways the offense can advance the ball:

and passing. In a typical play, the center passes the ball backwards and between their legs to the quarterback in a process known as the

. The quarterback then either hands the ball off to a running back, throws the ball, or runs with it. The play ends when the player with the ball is tackled or goes out-of-bounds or a pass hits the ground without a player having caught it. A forward pass can be legally attempted only if the passer is behind the line of scrimmage; only one forward pass can be attempted per down. As in rugby, players can also pass the ball backwards at any point during a play. In the NFL, a down also ends immediately if the runner's helmet comes off. The offense is given a series of four plays, known as downs. If the offense advances ten or more yards in the four downs, they are awarded a new set of four downs. If they fail to advance ten yards, possession of the football is turned over to the defense. In most situations, if the offense reaches their fourth down they will punt the ball to the other team, which forces them to begin their drive from farther down the field; if they are in

field goal range Field goal range is the part of the field in American football where there is a good chance that a field goal attempt will be successful. A field goal is normally 17 yards (7 yards in Canadian football) longer than the distance of the line of scrim ...

, they might attempt to score a field goal instead. A group of officials, the chain crew, keeps track of both the downs and the distance measurements. On television, a yellow line is electronically superimposed on the field to show the first down line to the viewing audience.

Kicking

Connor Barth attempts field goal 8 November 2015 151108-F-ID984-017

There are two categories of kicks in football: scrimmage kicks, which can be executed by the offensive team on any down from behind or on the line of scrimmage,NFL Rules 2012, p. 50.NCAA Rules 2011–2012, p. 34.NFHS Rules 2012, p. 32. and free kicks.NFL Rules 2012, p. 6.NCAA Rules 2011–2012, p. 30.NFHS Rules 2012, p. 27. The free kicks are the Kickoff (American football), kickoff, which starts the first and third quarters and overtime and follows a try attempt or a successful field goal; the safety kick follows a safety.NFL Rules 2012, pp. 8–9.NFHS Rules 2012, pp. 31–32. On a kickoff, the ball is placed at the 35-yard line of the kicking team in professional and college play and at the 40-yard line in high school play. The ball may be drop kicked or place kicked. If a place kick is chosen, the ball can be placed on the ground or a tee; a holder may be used in either case. On a safety kick, the kicking team kicks the ball from their own 20-yard line. They can punt, drop kick or place kick the ball, but a tee may not be used in professional play. Any member of the receiving team may catch or advance the ball. The ball may be recovered by the kicking team once it has gone at least ten yards and has touched the ground or has been touched by any member of the receiving team.NFL Rules 2012, pp. 29–30.NCAA Rules 2011–2012, pp. 61–64.NFHS Rules 2012, pp. 15, 46, 52–53. The three types of scrimmage kicks are place kicks, drop kicks, and punts. Only place kicks and drop kicks can score points. The place kick is the standard method used to score points, because the pointy shape of the football makes it difficult to reliably drop kick. Once the ball has been kicked from a scrimmage kick, it can be advanced by the kicking team only if it is caught or recovered behind the line of scrimmage. If it is touched or recovered by the kicking team beyond this line, it becomes dead at the spot where it was touched.NFL Rules 2012, pp. 33–34, 50–53.NCAA Rules 2011–2012, pp. 55–56, 63–64.NFHS Rules 2012, pp. 49, 53–54. The kicking team is prohibited from interfering with the receiver's opportunity to catch the ball. The receiving team has the option of signaling for a fair catch, which prohibits the defense from blocking into or tackling the receiver. The play ends as soon as the ball is caught and the ball may not be advanced.NFL Rules 2012, pp. 7, 54–55.NCAA Rules 2011–2012, pp. 30, 66–67.NFHS Rules 2012, pp. 27, 56.

Officials and fouls

First down measurement at EWU at Cal 2009-09-12

Officials are responsible for enforcing game rules and monitoring the clock. All officials carry a whistle and wear black-and-white striped shirts and black hats except for the referee, whose hat is white. Each carries a Penalty flag, weighted yellow flag that is thrown to the ground to signal that a Penalty (gridiron football), foul has been called. An official who spots multiple fouls will throw their hat as a secondary signal. The seven officials (of a standard seven-man crew; lower levels of play up to the college level use fewer officials) on the field are each tasked with a different set of responsibilities: * The referee is positioned behind and to the side of the offensive backs. The referee is charged with oversight and control of the game and is the authority on the score, the down number, and any rule interpretations in discussions among the other officials. The referee announces all penalties and discusses the infraction with the offending team's captain, monitors for illegal hits against the quarterback, makes requests for first-down measurements, and notifies the head coach whenever a player is ejected. The referee positions themselves to the passing arm side of the quarterback. In most games, the referee is responsible for spotting the football prior to a play from scrimmage. * The umpire is positioned in the defensive backfield, except in the NFL, where the umpire is positioned lateral to the referee on the opposite side of the formation. The umpire watches play along the line of scrimmage to make sure that no more than 11 offensive players are on the field before the snap and that no offensive linemen are Ineligible receiver downfield, illegally downfield on pass plays. The umpire monitors contact between offensive and defensive linemen and calls most of the Holding (American football), holding penalties. The umpire records the number of timeouts taken and the winner of the coin toss and the game score, assists the referee in situations involving possession of the ball close to the line of scrimmage, determines whether player equipment is legal, and dries wet balls prior to the snap if a game is played in rain. * The back judge is positioned deep in the defensive backfield, behind the umpire. The back judge ensures that the defensive team has no more than 11 players on the field and determines whether catches are legal, whether field goal or extra point attempts are good, and whether a pass interference violation occurred. The back judge is also responsible for the play clock, the time between each play, when a visible play clock is not used. * The head linesman/down judge is positioned on one end of the line of scrimmage. The head linesman/down judge watches for any line-of-scrimmage and illegal use-of-hands violations and assists the line judge with illegal shift or illegal motion calls. The head linesman/down judge also rules on out-of-bounds calls that happen on their side of the field, oversees the chain crew and marks the forward progress of a runner when a play has been whistled dead. First down marker

* The side judge is positioned twenty yards downfield of the head linesman. The side judge mainly duplicates the functions of the field judge. On field goal and extra point attempts, the side judge is positioned lateral to the umpire. * The line judge is positioned on the end of the line of scrimmage, opposite the head linesman. They supervise player substitutions, the line of scrimmage during punts, and game timing. The line judge notifies the referee when time has expired at the end of a quarter and notifies the head coach of the home team when five minutes remain for halftime. In the NFL, the line judge also alerts the referee when Two-minute warning, two minutes remain in the half. If the clock malfunctions or becomes inoperable, the line judge becomes the official timekeeper. * The field judge is positioned twenty yards downfield from the line judge. The field judge monitors and controls the

, counts the number of defensive players on the field and watches for offensive pass interference and illegal use-of-hands violations by offensive players. The field judge also makes decisions regarding catches, recoveries, the ball spot when a player goes out of bounds, and illegal touching of fumbled balls that have crossed the line of scrimmage. On field goal and extra point attempts, the field judge is stationed under the upright opposite the back judge. * The center judge is an eighth official used only in the top level of college football. The center judge stands lateral to the referee, the same way the umpire does in the NFL. The center judge is responsible for spotting the football after each play and has many of the same responsibilities as the referee, except announcing penalties. Another set of officials, the chain crew, are responsible for moving the chains. The chains, consisting of two large sticks with a 10-yard-long chain between them, are used to measure for a first down. The chain crew stays on the sidelines during the game, but if requested by the officials they will briefly bring the chains on to the field to measure. A typical chain crew will have at least three people—two members of the chain crew will hold either of the two sticks, while a third will hold the down marker. The down marker, a large stick with a dial on it, is flipped after each play to indicate the current down and is typically moved to the approximate spot of the ball. The chain crew system has been used for over 100 years and is considered to be an accurate measure of distance, rarely subject to criticism from either side.

Safety and brain health

Football is a full-contact sport, and injuries are relatively common. Most injuries occur during training sessions, particularly ones that involve contact between players. To try to prevent injuries, players are required to wear a set of equipment. At a minimum players must wear a football helmet and a set of Shoulder pads (sport), shoulder pads, but individual leagues may require additional padding such as thigh pads and guards, knee pads, chest protectors, and mouthguards.NFL Rules 2012, pp. 24–27.NCAA Rules 2011–2012, p. 22.NFHS Rules 2012, pp. 17–19. Most injuries occur in the lower extremities, particularly in the knee, but a significant number also affect the upper extremities. The most common types of injuries are strain (injury), strains, sprains, bruises, fractures, Joint dislocation, dislocations, and concussions. Repeated Concussions in American football, concussions (and possibly sub-concussive head impacts) can increase a person's risk in later life for CTE (chronic traumatic encephalopathy) and mental health issues such as dementia, Parkinson's disease, and Mood disorder, depression. Concussions are often caused by helmet-to-helmet or upper-body contact between opposing players, although helmets have prevented more serious injuries such as skull fractures. Various programs are aiming to reduce concussions by reducing the frequency of helmet-to-helmet hits; USA Football's "Heads Up Football" program aims to reduce concussions in youth football by teaching coaches and players about the signs of a concussion, the proper way to wear football equipment and ensure it fits, and proper tackling methods that avoid helmet-to-helmet contact. However, a study in the ''Orthopaedic Journal of Sports Medicine'' found that Heads Up Football was ineffective; the same study noted that more extensive reforms implemented by

and its member teams were effective in significantly reducing concussion rates. A 2018 study performed by the VA Boston Healthcare System and the Boston University School of Medicine found that tackle football before age 12 was correlated with earlier onset of symptoms of CTE, but not with symptom severity. More specifically, each year a player played tackle football under age 12 predicted earlier onset of cognitive, behavioral, and mood problems by an average of two and a half years.Age of First Exposure to Tackle Football and Chronic Traumatic Encephalopathy
, ''Annals of Neurology'', Michael L. Alosco PhD, Jesse Mez MD, MS, Yorghos Tripodis PhD, Patrick T. Kiernan BA, Bobak Abdolmohammadi BA, Lauren Murphy BA, Neil W. Kowall MD, Thor D. Stein MD, PhD, Bertrand Russell Huber MD, PhD, Lee E. Goldstein MD, PhD, Robert C. Cantu MD, Douglas I. Katz MD, Christine E. Chaisson MPH, Brett Martin MS, Todd M. Solomon PhD, Michael D. McClean ScD, Daniel H. Daneshvar MD, PhD, Christopher J. Nowinski PhD, Robert A. Stern PhD, Ann C. McKee MD, April 30, 2018.

Leagues and tournaments

The

(NFL) and the

(NCAA) are the most popular football leagues in the United States. The National Football League was founded in 1920 and has since become the largest and most popular sport in the United States. The NFL has the highest average attendance of any sporting league in the world, with an average attendance of 66,960 during the 2011 NFL season. The NFL championship game is called the Super Bowl, and is among the biggest events in club sports worldwide. It is played between the champions of the National Football Conference (NFC) and the American Football Conference (AFC), and its winner is awarded the Vince Lombardi Trophy. High School Football Game

College football is the third-most popular sport in the United States, behind professional baseball and professional football. The NCAA, the largest collegiate organization, is divided into three Divisions: NCAA Division I, Division I, NCAA Division II, Division II and NCAA Division III, Division III. Division I football is further divided into two subdivisions: the Football Bowl Subdivision (FBS) and the Football Championship Subdivision (FCS). The champions of each level of play are determined through NCAA-sanctioned playoff systems; while the champion of Division I-FBS was historically determined by various polls and ranking systems, the subdivision adopted a four-team playoff system in 2014. High school football is the most popular sport in the United States played by boys; over 1.1 million boys participated in the sport from 2007 to 2008 according to a survey by the National Federation of State High School Associations (NFHS). There is a stark contrast in youth football participation between boys and girls. Only one youth football league exists in the United States for girls, the Utah Girls Football League, GFL. The NFHS is the largest organization for high school football, with member associations in all List of states and territories of the United States, 50 states as well as the Washington, D.C., District of Columbia. USA Football is the governing body for youth and amateur football, and Pop Warner Little Scholars is the largest organization for youth football.

Other professional leagues

Several professional football leagues have been formed outside the auspices of the NFL.

Rival leagues

The most successful league to directly compete with the NFL was the American Football League (AFL), which existed from 1960 to 1969. The AFL became a significant rival in 1964 American Football League season, 1964 before signing a five-year, US$36 million television deal with NBC. AFL teams began signing NFL players to contracts, and the league's popularity grew to challenge that of the NFL. The two leagues merged in the 1970 NFL season, 1970 season, and all the AFL teams joined the NFL. An earlier league, the All-America Football Conference (AAFC), was in play from 1946 to 1949. After it had dissolved, two AAFC teams, the Cleveland Browns and the San Francisco 49ers, became members of the NFL; another member, the Baltimore Colts (1947–50), Baltimore Colts joined the league, but folded after just a year in the NFL. Other attempts to start rival leagues since the AFL merged with the NFL in 1970 have been far less successful, as professional football salaries and the NFL on television, NFL's television contracts began to escalate out of the reach of competitors and the NFL covered more of the larger cities. The World Football League (WFL) played for two seasons, in 1974 and 1975, but faced such severe monetary issues it could not pay its players. In its second and final season the WFL attempted to establish a stable credit rating, but the league disbanded before the season could be completed. The United States Football League (USFL) operated for three seasons from 1983 to 1985. Originally not intended as a rival league, the entry of owners who sought marquee talent and to challenge the NFL led to an escalation in salaries and ensuing financial losses. A subsequent US$1.5 billion antitrust lawsuit against the NFL was successful in court, but the league was awarded only $1 in damages, which was automatically tripled to $3 under antitrust law.

Complementary national leagues

The original XFL (2001), XFL was created in 2001 by Vince McMahon and lasted for only one season. Despite television contracts with NBC and UPN, and high expectations, the XFL suffered from low quality of play and poor reception for its use of Attitude Era, tawdry professional wrestling gimmicks, which caused initially high ratings and attendance to collapse. The XFL was rebooted in XFL (2020), 2020. However, after only five weeks of play, the league's operations slowly came to a close due to the ongoing COVID-19 pandemic in the United States, COVID-19 pandemic, and filed for bankruptcy on April 13. The United Football League (2009–2012), United Football League (UFL) began in 2009 UFL season, 2009 but folded after suspending its 2012 UFL season, 2012 season amid declining interest and lack of major television coverage. The Alliance of American Football lasted 2019 AAF season, less than one season, unable to keep investors.

International play

American football leagues exist throughout the world, but the game has yet to achieve the international success and popularity of

and

. It is not an Olympic sport, but it was a demonstration sport at the American football at the 1932 Summer Olympics, 1932 Summer Olympics. At the international level, Canada, Mexico, and Japan are considered to be second-tier, while Austria, Germany, and France would rank among a third tier. These countries rank far below the United States, which is dominant at the international level. NFL Europe, NFL Europa, the minor league, developmental league of the NFL, operated from 1991 to 1992 and then from 1995 to 2007. At the time of its closure, NFL Europa had five teams based in Germany and one in the Netherlands. In Germany, the German Football League (GFL) has 16 teams and has operated for over 40 seasons, with the league's championship game, the German Bowl, closing out each season. The league operates in a promotion and relegation structure with German Football League 2 (GFL2), which also has 16 teams. The BIG6 European Football League functions as a continental championship for Europe. The competition is contested between the top six European teams. The United Kingdom also operated several teams within NFL Europe during the League's tenure. The resulting rise in popularity of the sport brought the NFL back to the country in 2007 where they now hold the NFL International Series in London, currently consisting of four regular season games. The continuing interest and growth in both the sport and the series has led to the possible formation of a Potential London NFL franchise, potential NFL franchise in London An American football league system already exists within the UK, the BAFA National Leagues, BAFANL, which has run under various guises since 1983. It currently has 70 teams operating across the tiers of contact football in which teams aim to earn promotion to the Division above, with the Premier Division teams competing to win the Britbowl, the annual British Football Bowl game that has been played since 1985. In 2007 the British Universities American Football League was formed. From 2008, the BUAFL was officially associated with the

(NFL), through its partner organisation NFL UK. In 2012, BUAFL's league and teams were absorbed into BUCS after American football became an official BUCS sport. Over the period 2007 to 2014, the BUAFL grew from 42 teams and 2,460 participants to 75 teams and over 4,100 people involved. American football federations are present in IFAF Africa, Africa, IFAF Americas, the Americas, IFAF Asia, Asia, IFAF Europe, Europe and IFAF Oceania, Oceania; a total of 64 national football federations exist as of July 2012. The International Federation of American Football (IFAF), an international governing body composed of continental federations, runs tournaments such as the IFAF World Championship, the IFAF Women's World Championship, the IFAF U-19 World Cup, IFAF U-19 World Championship and the IFAF Flag Football World Championship, Flag Football World Championship. The IFAF also organizes the annual International Bowl game. The IFAF has received provisional recognition from the International Olympic Committee (IOC). Several major obstacles hinder the IFAF goal of achieving status as an Olympic sport. These include the predominant participation of men in international play and the short three-week Olympic schedule. Large team sizes are an additional difficulty, due to the Olympics' set limit of 10,500 athletes and coaches. American football also has an issue with a lack of global visibility. Nigel Melville, the CEO of USA Rugby, noted that "American football is recognized globally as a sport, but it's not played globally." To solve these concerns, major effort has been put into promoting flag football, a modified version of American football, at the international level.

Popularity and cultural influence

United States

"Baseball is still called the national pastime, but football is by far the more popular sport in American society", according to ESPN.com's Sean McAdam. In a 2014 poll conducted by Harris Insights & Analytics, Harris Interactive, professional football ranked as the most popular sport, and college football ranked third behind only professional football and baseball; 46% of participants ranked some form of the game as their favorite sport. Professional football has ranked as the most popular sport in the poll since 1985, when it surpassed baseball for the first time. Professional football is most popular among those who live in the eastern United States and rural areas, while college football is most popular in the southern United States and among people with graduate and post-graduate degrees. Football is also the most-played sport by high school and college athletes in the United States. In a 2012 study, the NCAA estimated there were around 1.1 million high school football players and nearly 70,000 college football players in the United States; in comparison, the second-most played sport, basketball, had around 1 million participants in high school and 34,000 in college. The Super Bowl is the most popular single-day sporting event in the United States, and is among the biggest club sporting events in the world in terms of TV viewership. The NFL makes approximately $10 billion annually. Super Bowl games account for seven of the top eight most-watched broadcasts in American history; Super Bowl XLIX, played on February 1, 2015, was watched by a record 114.4 million Americans. American football also plays a significant role in American culture. The day on which the Super Bowl is held is considered Super Bowl Sunday, a ''de facto'' national holiday, and in parts of the country like Texas, the sport has been compared to a religion. Football is also linked to other holidays; New Year's Day is traditionally the date for several college football bowl games, including the Rose Bowl Game, Rose Bowl. However, if New Year's Day is on a Sunday, the bowl games are moved to another date so as not to conflict with the typical NFL Sunday schedule. Thanksgiving (United States), Thanksgiving American football on Thanksgiving, football is an American tradition, hosting many high school, college, and professional games. Steve Deace of ''USA Today'' wrote that Americans are passionate about football "because it embodies everything we love about American exceptionalism. Merit is rewarded, not punished. Masculinity is celebrated, not feminized. People of various beliefs and backgrounds – a melting pot, if you will – must unify for a common goal for the team to be successful". Implicit rules such as playing through pain and sacrificing for the better of the team are promoted in football culture. The safety of the sport has also sparked national controversy in American popular culture. The 2015 film ''Concussion (2015 film), Concussion'' aimed to shed light on the sport's safety, specifically in the NFL by having Will Smith portray Bennet Omalu, Dr. Bennet Omalu, a neuropathologist who was the first to discover and publish findings of chronic traumatic encephalopathy or CTE.

Other countries

In Canada, the game has a significant following. According to a 2013 poll, 21% of respondents said they followed the NFL "very closely" or "fairly closely", making it the third-most followed league behind the National Hockey League (NHL) and Canadian Football League (CFL). American football also has a long history in Mexico, which was introduced to the sport in 1896. It was the second-most popular sport in Mexico in the 1950s, with the game being particularly popular in colleges. The ''Los Angeles Times'' notes the NFL claims over 16 million fans in Mexico, which places the country third behind the U.S. and Canada. American football is played in Mexico both professionally and as part of the college sports system. A professional league, the Liga de Fútbol Americano Profesional (LFA), was founded in 2016. NFL_International_Series_2010

Japan was introduced to the sport in 1934 by Paul Rusch, a teacher and Christian missionary who helped to establish football teams at three universities in Tokyo. Play was halted during World War II, but the sport began growing in popularity again after the war. , there are more than 400 high school football teams in Japan, with over 15,000 participants, and over 100 teams play in the Kantoh Collegiate Football Association (KCFA). The college champion plays the champion of the X-League (Japan), X-League (a semi-professional league where teams are financed by corporations) in the Rice Bowl to determine Japan's national champion. Suomi-ruotsi jenkkifutis

Europe is a major target for the expansion of the game by football organizers. In the United Kingdom in the 1980s, the sport was popular, with the 1986 Super Bowl being watched by over four million people (about 1 out of every 14 Britons). Its popularity faded during the 1990s, coinciding with the establishment of the Premier League—top level of the English football league system. According to BBC America, there is a "social stigma" surrounding American football in the UK, with many Brits feeling the sport has no right to call itself "football" due to the lack of emphasis on kicking. Nonetheless, the sport has retained a following in the United Kingdom; the NFL operates a media network in the country, and since 2007 has hosted the NFL International Series in London. Super Bowl viewership has also rebounded, with over 4.4 million Britons watching Super Bowl XLVI. The sport is played in European countries like Switzerland, which has American football clubs in every major city, and Germany, where the sport has around 45,000 registered amateur players. In American football in Brazil, Brazil, football is a growing sport. It was generally unknown there until the 1980s when a small group of players began playing on Copacabana Beach in Rio de Janeiro. The sport grew gradually with 700 amateur players registering within 20 years. Games were played on the beach with modified rules and without the traditional football equipment due to its lack of availability in Brazil. Eventually, a tournament, the Carioca championship, was founded, with the championship Carioca Bowl played to determine a league champion. The country saw its first full-pad game of football in October 2008. According to ''The Rio Times'', the sport is one of the fastest-growing sports in Brazil and is almost as commonly played as soccer on the beaches of Copacabana and Botafogo. Football in Brazil is governed by the Confederação Brasileira de Futebol Americano (CBFA), which had over 5,000 registered players as of November 2013. The sport's increase in popularity has been attributed to games aired on ESPN, which began airing in Brazil in 1992 with Portuguese commentary. The popularity and "easy accessibility" of non-contact versions of the sport in Brazil has led to a rise in participation by female players. According to ESPN, the American football audience in Brazil increased 800% between 2013 and 2016. The network, along with Esporte Interativo, airs games there on cable television. Football is often associated in Brazil as being the sport of supermodel Gisele Bündchen's husband Tom Brady. The NFL has expressed interest in having games in the country, and the Super Bowl has become a widely watched event in Brazil at bars and movie theaters.

Variations and related sports

, the predominant form of football in Canada, is closely related to American football—both sports developed from rugby and are considered to be the chief variants of gridiron football. Although both games share a Comparison of American and Canadian football, similar set of rules, there are several key rule differences: for example, in Canadian football the field measures , including two 20-yard end zones (for a distance between goal lines of 110 yards), teams have three downs instead of four, there are twelve players on each side instead of eleven, fair catches are not allowed, and a Single (football), rouge, worth a single point is scored if the offensive team kicks the ball out of the defense's end zone. The Canadian Football League (CFL) is the major Canadian league and is the second-most popular sporting league in Canada, behind the National Hockey League. The NFL and CFL had a formal working relationship from 1997 to 2006. The CFL has a strategic partnership with two American football leagues, the German Football League (GFL) and the Liga de Futbol Americano Profesional (LFA). The Canadian rules were developed separately from the American game. Indoor American football, Indoor football leagues constitute what ''The New York Times'' writer Mike Tanier described as the "most minor of minor leagues." Leagues are unstable, with franchises regularly moving from one league to another or merging with other teams, and teams or entire leagues dissolving completely; games are only attended by a small number of fans, and most players are semi-professional athletes. The Indoor Football League is an example of a prominent indoor league. The Arena Football League, which was founded in 1987 and ceased operations in 2019, was one of the longest-lived indoor football leagues. In 2004, the league was called "America's fifth major sport" by ''ESPN The Magazine''. There are several non-contact variants of football like flag football. In flag football the ballcarrier is not tackled; instead, defenders aim to pull a flag tied around the ballcarrier's waist. Another variant, Touch football (American), touch football, simply requires the ballcarrier to be touched to be considered downed. Depending on the rules used, a game of touch football may require the ballcarrier be touched with either one or two hands to be considered downed.

Notes

Footnotes

References

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External links

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National Football League

International Federation of American Football

NFL 360, an introductory website to football rules

Excerpts of a 1903 football game between the University of Chicago and University of Michigan
{{DEFAULTSORT:American Football American football, 1869 introductions American culture Ball games Team sports Sports originating in the United States Gridiron football variants