Football

American football, known in the United States simply as football and often as gridiron outside the United States, is a competitive team sport known for combining strategy with physical play. The objective of the game is to score points by advancing the ball into the opposing team's end zone. The ball can be advanced by carrying it (a running play) or by throwing it to a teammate (a passing play). Points can be scored in a variety of ways, including carrying the ball over the opponent's goal line, catching a pass thrown over that goal line, kicking the ball through the goal posts at the opponent's end zone, or tackling an opposing ball carrier within his end zone. The winner is the team with the most points when the time expires. American football is closely related to Canadian football, but with significant differences.[1] In the United States, the major forms are high school football, college football and professional football, which are essentially similar but feature slightly different rules.[2] High school football is governed in the U.S. by the National Federation of State High School Associations. College football is governed in the U.S. by two bodies; the National Collegiate Athletic Association and the National Association of Intercollegiate Athletics. The major league for professional football is the National Football League. Over the years, there have been other notable professional football leagues, including the All America Football Conference during the 1940s, the American Football League during the 1960s, the United States Football League during the 1980s, and the currently active United Football League. The sport is also played outside the United States. National professional and collegiate leagues exist in United Kingdom, Germany, Italy,[3] Switzerland,[4] Finland, Sweden,[5] Japan, Mexico, Israel,[6] Spain, Austria,[7] and several Pacific Island nations. The International Federation of American Football acts as an international governing body for the sport on five continents, but the organization has little standing in the United States compared to the other bodies and leagues mentioned above.

Field and players

American football is played on a field 360 by 160 feet (109.7 by 48.8 m).[13] The longer boundary lines are sidelines, while the shorter boundary lines are end lines. Sidelines and end lines are out of bounds. Near each end of the field is a goal line; they are 100 yards (91.4 m) apart. A scoring area called an end zone extends 10 yards (9.1 m) beyond each goal line to each end line. The end zone includes the goal line but not the end line.[13] While the playing field is effectively flat, it is common for a field to be built with a slight crown—with the middle of the field higher than the sides—to allow water to drain from the field. Yard lines cross the field every 5 yards (4.6 m), and are numbered every 10 yards from each goal line to the 50-yard line, or midfield (similar to a typical rugby league field). Two rows of short lines, known as inbounds lines or hash marks, run at 1-yard (91.4 cm) intervals perpendicular to the sidelines near the middle of the field. All plays start with the ball on or between the hash marks. Because of the arrangement of the lines, the field is occasionally referred to as a gridiron. At the back of each end zone are two goalposts (also called uprights) connected by a crossbar 10 feet (3.05 m) from the ground. For high skill levels, the posts are 18 feet 6 inches (5.64 m) apart. For lower skill levels, these are widened to 23 feet 4 inches (7.11 m). Each team has 11 players on the field at a time. Usually there are many more players off the field. There are at least 46 active players on an NFL team. However, if time allows, teams may substitute for any or all of their players during the breaks between plays. As a result, players have very specialized roles and are divided into three separate units: the offense, the defense and the special teams. Although this is rare, in some games, almost all of the players will play during the course of the game.

Start of halves

Similarly to association football, the game begins with a coin toss to determine which team will kick off to begin the game and which goal each team will defend. The options are presented again to start the second half; the choices for the first half do not automatically determine the start of the second half. The referee conducts the coin toss with the captains (or sometimes coaches) of the opposing teams. The team that wins the coin toss has three options:

1. They may choose whether to kick or receive the opening kickoff.

2. They may choose which goal to defend.

3. They may choose to defer the first choice to the other team and have first choice to start the second half. Whatever the first team chooses, the second team has the option on the other choice (for example, if the first team elects to receive at the start of the game, the second team can decide which goal to defend). At the start of the second half, the options to kick, receive, or choose a goal to defend are presented to the captains again. The team which did not choose first to start the first half (or which deferred its privilege to choose first) now gets first choice of options.

Advancing the ball

Advancing the ball in American football resembles the six-tackle rule and the play-the-ball in rugby league. The team that takes possession of the ball (the offense) has four attempts, called downs, in which to advance the ball at least 10 yards (9.1 m) toward their opponent's (the defense's) end zone. When the offense succeeds in gaining at least 10 yards, it gets a first down, meaning the team has another set of four downs to gain yet another 10 yards or to score. If the offense fails to gain a first down (10 yards) after 4 downs, the other team gets possession of the ball at the point where the fourth down ended, beginning with their first down to advance the ball in the opposite direction. Except at the beginning of halves and after scores, the ball is always put into play by a snap. Offensive players line up facing defensive players at the line of scrimmage (the position on the field where the play begins). One offensive player, the center, then passes (or "snaps") the ball backwards between his legs to a teammate behind him, usually the quarterback. Players can then advance the ball in two ways: 1. By running with the ball, also known as rushing. 2. By throwing the ball to a teammate, known as a pass or as passing the football. If the pass is thrown down-field, it is known as a forward pass. The forward pass is a key factor distinguishing American and Canadian football from other football sports. The offense can throw the ball forward only once during a down and only from behind the line of scrimmage. However, the ball can be handed-off to another player or thrown, pitched, or tossed sideways or backwards (a lateral pass) at any time. A down ends, and the ball becomes dead, after any of the following:

* The player with the ball is forced to the ground (a tackle) or has his forward progress halted by members of the other team (as determined by an official).

* A forward pass flies beyond the dimensions of the field (out of bounds) or touches the ground before it is caught. This is known as an incomplete pass. The ball is returned to the most recent line of scrimmage for the next down. * The ball or the player with the ball goes out of bounds.

* A team scores. Officials blow a whistle to notify players that the down is over. Before each down, each team chooses a play, or coordinated movements and actions, that the players should follow on a down. Sometimes, downs themselves are referred to as "plays."

Advancing the ball

A team scores points by the following plays:

* A touchdown (TD) is worth 6 points.[18] It is scored when a player runs the ball into or catches a pass in his opponent's end zone.[18] A touchdown is analogous to a try in rugby. Unlike rugby, a player does not have to touch the ball to the ground to score; a touchdown is scored any time a player has possession of the ball while the ball is on or beyond the opponents' goal line (or the plane above it). o After a touchdown, the scoring team attempts a try (which is also analogous to the conversion in rugby). The ball is placed at the other team's 3-yard (2.7 m) line (the 2-yard (1.8 m) line in the NFL). The team can attempt to kick it over the crossbar and through the goal posts in the manner of a field goal for 1 point (an extra point or point-after touchdown (PAT)[19]), or run or pass it into the end zone in the manner of a touchdown for 2 points (a two-point conversion). In college football, if the defense intercepts or recovers a fumble during a one or two point conversion attempt and returns it to the opposing end zone, the defensive team is awarded the two points.

* A field goal (FG) is worth 3 points, and it is scored by kicking the ball over the crossbar and through the goal posts (uprights).[18] Field goals may be placekicked (kicked when the ball is held vertically against the ground by a teammate) or drop-kicked (extremely uncommon in the modern game, with only two successes in sixty-plus years in the NFL). A field goal is usually attempted on fourth down instead of a punt when the ball is close to the opponent's goal line, or, when there is little or no time left to otherwise score.

* A safety, worth 2 points, is scored by the opposing team when the team in possession at the end of a down is responsible for the ball becoming dead behind its own goal line. For instance, a safety is scored by the defense if an offensive player is tackled, goes out of bounds, or fumbles the ball out of bounds in his own end zone.[18] Safeties are relatively rare. Note that, though even more rare, the team initially on offense during a down can score a safety if a player of the original defense gains possession of the ball in front of his own goal line and then carries the ball or fumbles it into his own end zone where it becomes dead. However, if the ball becomes dead behind the goal line of the team in possession and its opponent is responsible for the ball being there (for instance, if the defense intercepts a forward pass in its own end zone and the ball becomes dead before the ball is advanced out of the end zone) it is a touchback: no points are scored and the team last in possession keeps possession with a first down at its own 20 yard line. In amateur football, in the extremely rare instance that a safety is scored on a try, it is worth only 1 point.

Penalties

Fouls (a type of rule violation) are punished with penalties against the offending team. Most penalties result in moving the football towards the offending team's end zone. If the penalty would move the ball more than half the distance towards the offender's end zone, the penalty becomes half the distance to the goal instead of its normal value. Most penalties result in replaying the down. Some defensive penalties give the offense an automatic first down. Conversely, some offensive penalties result in loss of a down (loss of the right to repeat the down). If a penalty gives the offensive team enough yardage to gain a first down, they get a first down, as usual.

If a foul occurs during a down, an official throws a yellow penalty flag near the spot of the foul. When the down ends, the team that did not commit the foul has the option of accepting the penalty, or declining the penalty and accepting the result of the down.

Outside the United States

Outside the United States, the sport is referred to as "American football" (or a translation thereof) to differentiate it from other football codes such as association football (soccer), rugby football, Australian rules football and Gaelic football. In Australia and New Zealand the game is also known as gridiron football, or more commonly as gridiron,[31][32] although in the United States the term gridiron refers only to the playing field itself.[33] The term gridiron has also been used in the UK to describe the game.[34] In much of the world, the term football is unambiguous and refers to association football (known commonly as 'soccer' in the United States). The NFL has attempted to introduce the game to other nations and operated a developmental league, NFL Europa, with teams in five German cities and one in the Netherlands, but this league folded following the 2007 season. The professional Canadian Football League and collegiate Canadian Interuniversity Sport play under the only slightly different Canadian rules. In the UK, 46 teams play in the British American Football League. The BAFL has three levels: The Premier, of which there are five teams; BAFL 1, of which there are 19 teams; and BAFL 2, of which there are 26 teams. While the lower level teams have their own championship games during BritBowl Weekend, only Premier league teams face each other in the BritBowl which is it held in Doncaster's Keepmoat Stadium. Unlike the NFL, the BAFL season is played through the summer (April to September), with the British university season spanning the autumn and winter. In Mexico, the ONEFA is a college league with 26 teams in 3 conferences. In Japan, the X-League is a professional league with 60 teams in four divisions, using promotion and relegation. After the post-season playoffs, the X-League champion is determined in the Japan X Bowl. There are also over 200 universities fielding teams, with the national collegiate championship determined by the Koshien Bowl. The professional and collegiate champions then face each other in the Rice Bowl to determine the national champion. In Germany, the German Football League has 12 teams partitioned into north and south conferences. The finalists from the playoffs determine the German champion during the German Bowl.