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American football
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American football

American football, known in the United States as simply football, is a competitive team sport that rewards players' speed, agility, tactics, and brute strength as they push, block, tackle, chase, and outrun each other, trying to force a ball further into their opponent's territory for one hour of game time, which translates into three to four hours of real time.

Like most team sports (and individual sports in the context of a meet like the Olympics), American football is often seen as a metaphor for war. It is one of the more physically demanding sports, as there is a great deal of physical contact occurring on every play as players often weighing 300 pounds or more shove each other with every ounce of their strength, and with a clearly defined front line, moving up and down the field, separating the offensive and defensive squads.

American football does not much resemble soccer, the sport which most of the world calls "football". However, both of these games have their origins in varieties of football played in England in the mid-19th century, and American football is directly descended from rugby football, usually known simply as "Rugby". The US game still has some things in common with the two varieties of rugby, especially rugby league.

Table of contents
1 Popularity
2 Naming
3 Professional, college, and other leagues
4 The game
5 The field
6 Play of the game
7 Advancing the ball
8 Specialized units and players
9 Penalties
10 Development of the game
11 Beyond recreation and entertainment
12 See also
13 External links


Football is extremely popular in the US. Since the 1990s it has surpassed even baseball as the nation's most popular spectator sport. The professional league, the National Football League (NFL), which consists of 32 teams, is very popular. Its championship game, the Super Bowl, is annually watched by nearly half of US television households, and is also televised in over 150 other countries.

College football is extremely popular, with many major colleges and universities playing NCAA (National Collegiate Athletic Association) Division I football, and consistently selling out huge stadiums. College games are widely televised and widely watched. Many colleges in lower NCAA divisions and the National Association of Intercollegiate Athletics (NAIA) have varsity football teams, as do most high schools. There are also amateur, club and youth teams (such as teams in the Pop Warner leagues). In addition to those leagues and teams, now there is an American Football World Cup. In addition, there are many "semi-pro" teams, meaning the players are paid to play, but at a small enough salary that they generally must also have a full-time, more traditional job.


The word football has a number of different meanings. In the United States football almost always means what, in the rest of the English-speaking world, is usually called American football (or in some cases Gridiron football). In most of the rest of the world, the word football means the game that is called soccer in the US, although it is occasionally called Association football or International football. Soccer, the most popular form of football world-wide, is also popular in the US, particularly as a participation sport for children. It is played at all levels, youth, amateur, high school, college and professional, and in internationals by teams involving both sexes (see: football (soccer))

The name football might seem a curious name for the sport of American football, as the players' feet rarely have much to do with the ball -- kicking the football is only allowed in certain situations and is most often inadvisable. The vast majority of game time involves players holding the ball in their hands as they run. However, the sport is a direct descendant of rugby union football (which in turn descended from soccer), as explained below, and has retained the name.

In the remainder of this article, the word football refers to American football.

Professional, college, and other leagues

Football is played at a number of levels in the United States and abroad. These include the following. The descriptions on this page are based primarily on the current rules of the National Football League (NFL, 1920-present). Differences with college rules will be noted.

Professional, college, high school, and amateur rules are similar. The minor Arena Football League (1987-present) plays an indoor adaptation of American football, at a faster pace, on a smaller field with no built-in sidelines -- the edges of the grid are coincident with padded walls similar to those found in a baseball outfield. Flag football and touch football are non-tackle versions of American football.

Professional leagues that no longer exist include the World Football League (WFL,1974-75), the United States Football League (USFL,1983-1985), the XFL (XFL,2001), the All-America Football Conference (1946-1949), the World League of American Football (WLAF,1991-1993-now NFL Europe), and, the American Football League (AFL,1960-1969). Since 2000, there has been a surge of women's professional leagues.

The game

Play in American football consists of a series of individual plays of short duration, between which the ball is not in play. Substitutions are allowed between plays, which allows for a great deal of specialization, as coaches put in players they think are best suited for any particular situation. The game is very tactical and strategic. With 22 players on the field at a time, (eleven on each team), each with an assigned task for a given play, the strategies are complex.

Object of the game

The object of the game is to advance the ball to the opponents' end of the field and score points. The team with the most points when time has expired wins.

Duration, kickoffs and free kicks

The game is 60 minutes long, divided into two halves separated by a halftime. Each half consists of two quarters, each 15 minutes long. Teams change ends of the field after the first and third quarters. If a game is tied at the end of regulation, overtime is played. Professional overtime periods are "sudden death", meaning that the teams that scores first, by any means, wins. In college football, an overtime procedure ensures that each team has equal opportunity to score.

A kickoff is a special play used to start each half, and also used to restart the game following a field goal, or a conversion attempt following a touchdown. One team kicks the ball, usually from its own 30-yard line, although a kickoff may occur elsewhere due to a penalty on the preceding play. (Note: the ball is usually kicked from the 35 yard line in college football). The ball must be kicked from the ground (not punted) and in bounds at least 10 yards away. Once the ball has traveled 10 yards upfield it can be fielded by either team. The ball is usually just kicked deep to the receiving team, but sometimes a team will attempt to recover its own kick, in a play that is known as an onside kick.

A free kick is used to restart the game following a safety, which doesn't happen often. The team that was trapped in its own end zone, and therefore conceded two points to the other team, kicks the ball from its own 20-yard line. A free kick may be punted if the kicking team so chooses.

Methods of scoring

Points can be scored in the following ways.

The field

to the nearest end zone.]]

The field is a rectangle 120 yards (109.73 metres) long and 53 1/3 yards (48.78 metres) wide, defined by sidelines running the length of the field and endlines running the width. There is a goal line ten yards in from each end line and parallel to it. The two goal lines are thus 100 yards (91.44 metres) apart. The area of the field between the goal lines is called the field of play. At each end of the field, the end zone is the area between the goal line and the end line.

Within the field of play, additional markings include yard markers, as well as inbound lines (also called hash marks), every yard the length of the field. The inbound lines (hash marks), which are short lines perpendicular to the yard markers, differ in distance from the sidelines at each main level of the game:

Every 5 yards, the yard markers run the width of the field, and every 10 yards, they are marked by numbers indicating the distance, in yards, from the nearest goal line.

At the center of each end line is a set of goal posts, which have two upright posts extending above a crossbar. The distance between upright posts is 18-1/2 feet (23 feet 4 inches in high schools), and the top of the crossbar is 10 feet above the ground.

Play of the game

A game consists of many individual plays. The vast majority of these are scrimmage plays. Each play from scrimmage is one of a series of downs given to the team with possession. These two concepts, the concept of scrimmage, and the concept of downs, are fundamental to American football, and are what distinguish it, as well as Canadian football, from most other forms of football. However, rugby league does have a similar system where each side is allowed to be tackled five times while in possession (see the entry for rugby league for an explanation of the play-the-ball and the limited tackles rule).

A set of downs begins with a first down, which is given to a team either after it has just gained possession on the previous play, or it has gained the necessary yardage from a previous set of downs. On a first down, the team with possession is given four downs to gain 10 yards (they have "a first and ten", meaning that it is first down, and they need ten yards to get another first down). The line a team must reach in order to gain a first down is technically called the line to gain, although it is commonly called first down yardage. The team with possession is called the offensive team, and the other team the defensive team.

Plays from scrimmage

down is a play from scrimmage.  Prior to each play from scrimmage, the two teams line up on opposite sides of a line of scrimmage, which is defined by the spot of the ball from the previous play. The spot is, in most cases, the yard line at which the ball became dead on the previous play, plus or minus any penalty yardage. A down, or play from scrimmage, begins with a snap and ends when the ball becomes dead for any reason. A snap is either a handoff between the legs from the center to the quarterback, or it is a pass between the legs from the center to the quarterback, or possibly to a player other than the quarterback, such as a punter or a holder for a field goal attempt. The ball may become dead, ending the down, because a player in possession is tackled, or because his forward progress is stopped, or because he goes out of bounds, or because a forward pass goes incomplete.

Advancing the ball

There are two methods that can be used to advance the ball while still maintaining possession:

It is important for the offense to run a variety of running and passing plays in order to keep the defense uncertain of the next play. If the quarterback has two broken fingers on his throwing hand, for example, the defense can safely risk lining up in a run defense for nearly every play, which should successfully squelch the offense's running backs.

Fourth down situations

If a team uses all four of its downs without gaining the yardage for a first down, possession goes to the other team. Fourth down situations are therefore pivotal. The offense has three choices: "go for it", punt, or attempt a field goal.

Things the offense may decide to do on fourth down:

A team will occasionally run a trick play on fourth down. They will line up as if to punt or attempt a field goal, but will instead run the ball or pass it in an attempt to pick up a first down.

Specialized units and players

With its unlimited substitutions, American football is highly specialized, with most teams having three specialized units: an offensive unit, a defensive unit, and special teams. There are many specialized players within each units. Some players may only be used in certain situations. (for details see: offensive unit, defensive unit, special teams.)


Some of the more common penalties are listed below. In most cases the offending team will be assessed a penalty of 5, 10 or 15 yards, depending on the infraction. There may also be a loss of down for a penalty against the offense. A penalty against the defense may result in an automatic first down. In some cases, the offense will be given the option of declining the penalty and taking the yardage gained on the play. For some infractions by the defense, the penalty is applied in addition to the yardage gained on the play. Most of a number of personal fouls, which involve danger to another player, carry 15-yard penalties.

No penalty may move the ball more than half the distance to the goal line, in either direction. The only exception to this rule is defensive pass interference; see the discussion of that penalty for more details.

Note: The neutral zone is the space defined by lines drawn through the ends of the ball parallel to the yard lines when the ball is spotted and ready for play. No player may legally have any part of his body in the neutral zone when the ball is snapped, with the exception of the center.

Penalties against the offense

Penalties against the defense

At any level, if the receiver is interfered with behind the line of scrimmage, the defender cannot be charged with pass interference (although he may be guilty of a different penalty). This nuance in the rules almost never arises, but can conceivably occur on a screen pass.

Penalties against either team

Development of the game

American football in its current form grew out of a series of three games between Harvard University and McGill University of Montreal in 1874. McGill played rugby football while Harvard played the Boston Game, which was closer to soccer. As often happened in those days of far from universal rules, the teams alternated rules so that both would have a fair chance. The Harvard players liked having the opportunity to run with the ball, and in 1875 persuaded Yale University to adopt rugby rules for their annual game. In 1876 Yale, Harvard, Princeton, and Columbia formed the Intercollegiate Football Association, which used the rugby code, except for a slight difference in scoring.

In 1880 Walter Camp introduced the scrimmage in place of the rugby scrum. In 1882 the system of downs was introduced to thwart Princeton's and Yale's strategy of controlling the ball without trying to score. In 1883 the number of players was reduced, at Camp's urging, to eleven, and Camp introduced the soon standard arrangement of a seven-man offensive line with a quarterback, two halfbacks, and a fullback.

On September 3, 1895 the first professional football game was played, in Latrobe, Pennsylvania, between the Latrobe YMCA and the Jeannette Athletic Club. (Latrobe won the contest 12-0.).

By the 1890s interlocking offensive formations such as the flying wedge had made the game extremely dangerous. Despite restrictions on the flying wedge and other precautions, in 1905 eighteen players were killed in games. President Theodore Roosevelt informed the universities that the game must be made safer.

In 1906, two rival organizing bodies, the Intercollegiate Rules Committee and the Intercollegiate Athletic Association, met in New York; eventually they agreed on several new rules intended to make the game safer, among them the addition of a neutral zone between the scrimmage lines and a requirement that at least six players from each team line up on them. The most far-reaching innovation they considered, though, was the legalization of the forward pass. This was very controversial at the time, much derided by purists. As an alternative means of opening out the play, Walter Camp would have preferred widening the field; but representatives from Harvard pointed to recently constructed Harvard Stadium, which could not be widened, and the forward pass was adopted; it has come to shape the whole history of American football, as opposed to its cousins around the world.

In 1910, after further deaths, interlocking formations were finally outlawed; and in 1912 the field was changed to its current size, the value of a touchdown increased to 6 points, and a fourth down added to each possession. The game had achieved its modern form.

Beyond recreation and entertainment

Football and drugs

Contemporary football players are larger than their predecessors of only 30 or 40 years ago. It is quite normal, for instance, for all the members of the offensive line of a major college or professional team to weigh more than 300 pounds (136 kg.), whereas in the 1960's linemen who weighed only 270 pounds were common. The increase in player size has led to a increase in the frequency and severity of injuries.

Since nutritional standards and weight-training technique were already quite advanced even in the 1960's, it has been conjectured that much of the increase in the size of the players is the result of the widespread availability of illegal anabolic steroids, which facilitate increased growth of muscle tissue. Such drugs are widely available even to high school players.

Because anabolic steroids have dangerous side effects, the National Football League tests its players for steroids, and penalizes those who are caught. However, it has recently emerged that new varieties of steroids are being developed in clandestine laboratories, which elude existing drug tests. Hence there is a kind of "arms race" between the scientists who develop new kinds of illegal steroids and those who develop tests to detect them.


Despite the helmets and heavy padding worn by all players on the field, injuries are common in football. An "Injury Report" section is ubiquitous in American newspapers' sports sections, detailing, for each injured player on each team, his injury and the amount of time he is expected to be out. Twice-weekly during the season (Wednesdays and Fridays), all NFL teams must report the status of their injured players, or be subject to a fine from the league. The standard severity descriptions are "out" (will not play in the coming game); "doubtful" (25% chance of playing); "questionable" 50% chance of playing); or "probable" (75% chance of playing). Note that teams occasionally manipulate their injury reports, minimizing or maximizing the extent of a player's injury, as an attempt to strategically deny their upcoming opponents a clear picture of the team's health. Similar systems are in place for most major American sports.

The NFL has a roster limit of 53 players per team during the season; 45 of which dress for a game plus an "emergency quarterback" who only plays if all the quarterbacks on the 45-man roster are out of the game. Players who are injured are frequently among the eight that do not dress. If it becomes certain that a player will not play for the rest of the season, the team may put him on the "Injured Reserve" list and replace the player on the roster.

An average of about eight players die each year in the United States as a result of injuries received in games at all levels. About 160 concussions occur every season, and the National Football League now collects benchmark measures of awareness for each player, which can be used during a game to judge whether he has been concussed.

Injuries sustained by football players often are permanent. Many former football players experience pain, sometimes severe, that lasts for the rest of their lives. Many players require surgery, even multiple surgeries, for injuries experienced years earlier.

Interestingly, newspaper reporters who have interviewed former football players who are crippled or in pain as a result of their former sport find that a player will never (or virtually never) express regret over his choice of career. The players often state that the thrill of playing football was worth the price of a lifetime of subsequent pain.

Deaths and long-term disability attributed to illegal use of anabolic steroids have become a new factor in this picture, starting in about the 1990s.

Instances of heat-related death, especially during professional practice sessions, have begun receiving press attention in the decade of the 2000s, and led to new standards intended to respond cautiously to possible danger signs that traditionally had been ignored. There is also the prospect that conventional first-aid technique has been in error, and an apparatus to circumvent this: apparently efforts to cool an overheated patient quickly, by wetting a large fraction of the body, are misguided, with the sudden chilling of the skin causing the body to reduce superficial circulation, and making that chilling near the surface ineffective at cooling the core of the body and thus the brain. A device suitable for professional teams has been developed, that provides for rapid cooling of small areas of skin where large blood vessels are near the surface, and is proposed as a means of cooling the blood quickly without evoking the reflex of isolating the body surface from the core.

What's it all about?

Football is in many ways a sport apart, among those traditional in America. George Carlin has monologized at length on its contrasts with baseball, which is traditionally called "the American pastime": Football is about "ground control" and played on a "gridiron" of exact dimensions, while baseball is about "going home", and played in "parks" that are all different from one another, and so on. Such observations, however humorous, would be widely regarded as at least hints about some of the nature and significance of the game.

Character building

It is a widespread American doctrine that participation in team sports, including football in particular, inculcates worthwhile habits and values in the players. Leadership (at least for quarterbacks and exemplary players), identification with a group, aggressiveness where called for, the setting of personal goals, and sustaining commitment to these, are often mentioned.

Football scandals

There is a long history in the second half of the
20th century of controversy over the tension in college football between values important to the institutions' academic missions and the team's win-and-loss record. Many observers attribute to football skill a excessive role in winning admission for prospective players; they by and large regard this as an ongoing scandal. Measures that are seen as effective in maintaining players' academic eligibility but not in furthering their graduation or competence in their fields of study attract similar criticism.

In the decade of the 2000s, the increasing economic stakes in sports, changed attitudes outside football regarding acceptable behaviour towards women, and the perception of uncontrolled use of steroids, all have played a part in an increase in public concern about football's role. Many suggest that the status and other rewards accruing to players encourages arrogance in general, and in particular, both an assumption of privilege and an expectation of immunity from consequences. It is also suggested that

This issue came to a head early in 2004 during a series of sex scandals that rocked the football program at the University of Colorado. The school's head football coach, Gary Barnett, in responding to the charge by his only female player that a teammate had raped her, accused her of being an incompetent player. Almost immediately after his remarks, Barnett was placed on administrative leave, but was later reinstated after a committee that reviewed the Colorado football program placed most of the blame for the scandals on higher-ups. The aggressive image of football and the amounts of money involved can support the perception of its being the "last bastion" of sports administrators likely to wink at abuses; close scrutiny and drawing of parallels with Barnett can be expected in any case that is claimed to suggest coddling anti-social players.

See also

External links

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