How football is played

The playing time in college and professional football games is 60 minutes. High school games last 48 minutes. A game is divided into halves. Each half, in turn, consists of two periods called quarters. An intermission, called half-time, lasts about 20 minutes between halves. There are also 1-minute or 2-minute rest periods after the first and third quarters. At the end of each quarter, teams change goals.

The official time clock is stopped only (1) after an incomplete pass, (2) if a player is injured, (3) after a team scores, (4) if a ball carrier goes out of bounds, or (5) if a player on either team or an official calls a time out. Each team may call up to three time outs each half. Time outs last 90 seconds in high school and college games and 2 minutes in NFL games. In college games, the clock is also stopped briefly after each first down to move the first down markers. During the final 2 minutes of NFL games, the clock is stopped after some plays while the ball is placed in position for the next play.

The kickoff starts each half of a football game. A team also kicks off after it scores a touchdown or a field goal.

The team that kicks off to begin the game is decided by a toss of a coin at midfield. The visiting team calls "heads" or "tails." The team that wins the toss may (1) make the kickoff, (2) receive the kickoff, or (3) select the goal it wishes to defend. In most cases, teams choose to receive the opening kickoff to get the first chance at scoring. The team that loses the coin toss gets the choice of kicking, receiving, or defending either goal when the second half begins.

The kickoff is made from the 40-yard line in high school games, the 35-yard line in college games, and the 30-yard line in NFL games. Most kickers place-kick the ball. Beforekicking the ball, they stand it on an angle on a tee.

The kicker's teammates stand in a line across the field until the ball is kicked. Generally, the receiving team places two fast runners near its goal line. The runner nearest the ball catches it and runs it back toward the other team's goal. The kick returner's teammates try to block the opposing players, who are running down the field to tackle him.

After a kickoff travels 10 yards, it becomes a free ball--that is, either team may recover it. Normally the kicker tries to kick the ball as far down the field as possible. Occasionally, the kicker will kick the ball only a short distance to give his team a chance to recover the ball before the receiving team does. This maneuver is called an onside kick.

The ball is ruled dead if it is kicked beyond the end zone or if the kick returner catches it in the end zone and touches the ground with his knee. A touchback is then called, and the ball is put in play on the receiving team's 20-yard line. The kick returner is ruled down if he goes out of bounds or if any part of his body except his feet or hands touches the ground. In the NFL, the kick returner must be downed by an opponent. If the returner slips and falls but is not touched by an opposing player, he may get up and advance the ball until he is tackled or goes out of bounds.

Advancing the ball. After the kick returner has been downed, the ball is placed at the point where the return ended. The offensive and defensive teams then come on the field.

The offense has four plays, called downs, to advance the ball at least 10 yards by running or passing. If the offense gains 10 yards, it gets a first down. If the team fails to make a first down, it loses possession of the ball. Each time the team gets a first down, it receives another four downs to gain 10 yards. In high school and college games, the offensive team has 25 seconds to put the ball in play after the referee has signaled play to begin. In the NFL, the offense has 30 seconds.

Before a play begins, each team gathers in a huddle behind its side of the line of scrimmage. In the offensive huddle, the quarterback names his team's next play, the formation to be used, and the number or color he will call out to signal the center to snap the ball. In the defensive huddle, a formation is called that the team hopes will stop the offensive play.

After the teams have huddled, they line up facing each other along the line of scrimmage. The center begins the play by snapping the ball to the quarterback. The quarterback then hands or pitches (tosses) the ball to a running back, runs with it himself, or throws a pass. The offense directs running plays around either end, between the end and the tackle, between the tackle and the guard, or between the guard and the center.

On a passing play, the passer is usually the quarterback. Occasionally, another back or even an end will throw the ball. The passer must throw from behind the line of scrimmage. Only the ends and backs may catch a pass. The tackles, guards, and center must stay behind the line of scrimmage until the ball is thrown. They may then run down-field and block for the pass receiver.

If a defensive player catches a pass, it is called an interception. The defensive player may return the ball toward the opponent's goal until he is downed or goes out of bounds. His team's offensive players then come on the field and try to score.

The defense may also gain possession of the ball by recovering a fumble. A fumble occurs if an offensive player drops the ball. In high school and college football games, a defensive player may run with a fumble only if he catches the ball before it hits the ground. If the player recovers the ball after it hits the ground, his team gets the ball at that spot. In the NFL, a defensive player may run with a fumble after it hits the ground.

If the offensive team does not make a first down inthree plays, it usually punts the ball on fourth down. A punt gives possession of the ball to the other team. If the offense tries to make a first down on fourth down and fails, the other team gets the ball where the play ends. Any offensive player may punt. The kicker stands 10 to 12 yards behind the center, who snaps the ball to him for the punt. A long or well-aimed punt can force the opposing team to start its offense deep in its own side of the field.

Scoring. A team earns points by scoring (1) a touchdown, (2) a conversion, (3) a field goal, and (4) a safety.

Touchdown. A touchdown earns six points. The offense scores nearly all touchdowns. It does so by running the ball or catching a pass over the opposing team's goal line. Occasionally, the defense scores a touchdown through an interception or a fumble or by recovering a blocked punt in the end zone.

Conversion. Immediately after a touchdown, the scoring team tries for a conversion, also called the extra point or point after touchdown. Before a conversion attempt, the ball is placed on the 2-yard line in NFL games and on the 3-yard line in high school and college games. A kicker scores one point by place kicking the ball over the crossbar and between the goal posts. The offense can score a two-point conversion by running or passing the ball over the goal line. In college games, the defensive team scores two points if it blocks the conversion kick, recovers a fumble, or intercepts the pass and then advances the ball into the opponent's end zone.

Field goal. A field goal is worth three points. It is scored by place kicking the ball over the crossbar and between the goal posts. The kick may be made from anywhere on the field. If the field goal is missed, the defensive team gets possession of the ball. In high school games, the ball is placed on the 20-yard line. In college games, the ball is returned to the line of scrimmage or to the 20-yard line if the line of scrimmage was inside the 20. In the NFL, the ball is placed where the kick was tried, about 7 yards behind the line of scrimmage.

Safety. Only the defense can score a safety, which counts two points. The defense earns a safety if it tackles the ball carrier in his own end zone, if the ball carrier steps out of the back or side of his end zone, or if a blocked punt goes out of the end zone.

The officials supervise the football game and enforce the rules. Each official has particular duties, but any of the officials may call a rule violation.

The chief official is the referee, who has general charge of the game. He has the final word on all rulings. The referee stands behind the offensive backfield. The umpire is positioned behind the defensive line and watches for violations in the line. The head linesman stands at one end of the line of scrimmage. He marks the forward progress of the ball and supervises the sidelines crew, which keeps track of the downs and the yardage needed for a first down. The field judge stands behind the defensive secondary in the middle of the field. He watches for violations on punt returns and pass plays down-field. The back judge is positioned behind the defensive secondary near a sideline. His job is to spot violations between the defensive backs and the offensive pass receivers. The line judge stands opposite of the head linesman and, like the umpire, watches for violations in the line. The line judge is also the official timekeeper. The NFL also uses a side judge. He stands opposite the back judge and on the same side of the field as the head linesman. The side judge has the same responsibilities as those of the back judge.

Violations and penalties are called when players break the rules. An official signals a violation by throwing a yellow cloth, called a flag, in the air. In most cases, a violation occurs during a play, and the officials allow the play to be completed. The referee then explains the violation to the captain of the team that was fouled. The captain has two choices. He may accept the penalty to be imposed on the team that committed the foul. Or he may refuse the penalty and accept the completed play. If he accepts the penalty, it is enforced and the down is usually replayed. If he accepts the play, the penalty is disregarded. A team is penalized for a violation with a loss of yardage and, in some cases, also the loss of a down. Common violations include (1) clipping, (2) holding, (3) offside, (4) interference, (5) roughing, and (6) illegal procedure.

Clipping is committed if an offensive player blocks a defensive player from behind beyond the line of scrimmage. The penalty is 15 yards.

Holding is called against an offensive player who uses his hands to block a defensive player. In high school and college games, a defensive player is penalized for holding if he uses his hands except to tackle a ball carrier. In the NFL, a defensive player may use his hands under certain conditions. The penalty is 10 yards for offensive holding and 5 yards for defensive holding. In the NFL, defensive holding also includes an automatic first down for the offense.

Offside is called if any part of a player's body is beyond the line of scrimmage when the ball is snapped. The penalty is 5 yards.

Interference is ruled if the pass receiver or pass defender is blocked, tackled, or shoved while the ball is still in the air. In defensive interference, the offense gets the ball at the spot of the foul and receives a first down. In offensive interference, the offense is penalized 15 yards and a down.

Roughing is a foul committed against a kicker or passer. The defense may not tackle or bump a kicker while he is in the act of punting or place kicking. The defense may tackle a passer only while he has the ball. The player may not be hit after he throws the pass. The penalty for roughing a kicker or passer is 15 yards and an automatic first down.

Illegal procedure is called if the offense does not have seven players on the line of scrimmage or if an offensive player moves forward before the ball is snapped. Illegal procedure is also called if the offense or defense has more than 11 players on the field. The penalty is 5 yards.