Field Features
The field is 110 yards long and 65 yards wide. The middle of the field is the 55 yard line. The field is lined every 10 yards. Each team claims half of the field. The "zero yard line" is called the goal line. The areas at each end of the playing field, extending 20 yards past the goal lines, are called the end zones. Teams try to get the ball past the opponent's goal line into the end zone to score a touchdown. Goal posts are positioned at line of each end zone, which, together with the cross bar, look like a big “H” or “Y”. The goal posts are only used when a team attempts a field goal instead of going for a touchdown or to kick for extra points after scoring a touchdown. To score a field goal or complete a conversion, the ball must go between the vertical posts and over the bar. In the other direction, the field is divided into three parts, left, center and right, by the hash marks. Normally, for each play, the ball starts where it ended up at the end of the previous play. If the ball is stopped outside of the centre section of the field, it is brought back to the nearest hash mark, so plays never starts at the extreme sides of the field. The area to either side of the field is out-of-bounds.
Game Features
At the start of the game there is a coin toss to determine which team gets possession of the ball first. The team that has the ball is the offense; the other team is the defense. The total playing time for a football game is approximately one hour (or less depending upon the division), but takes about two hours to play because the clock is often stopped for various reasons. The game is divided into 15 or 12 minute quarters, depending on the division level. At the end of the second quarter there is also a 15 or 12 minute pause that is called half time. At the end of the first and third quarters, the players merely switch sides. This switching of sides evens up any advantage due to the sun or wind. The players leave the field at half time. After half time, the ball is moved to the corresponding point on the other side of the field and play continues. The team that originally lost the coin toss gets to have the ball first following another kickoff.
Kickoff:
At the start of each half and after each touchdown or field goal (when it's time to let the other team have the ball), the defending team starts by placing the ball on a tee at their 45 yard line and kicking the ball toward the other team. This is a kickoff. The other team tries to catch the ball and run it back as far as possible. If the ball is kicked into the end zone and no one catches it or the player catching it does not run with it, a "rouge ' (1 point) is scored for the kicking team and the first play starts at the offense's 35 yard line.
Downs
The offense has 4 plays or downs to cover 10 yards or more. A play ends when the player with the ball is either stopped or goes out-of-bounds, or if the ball is thrown and missed which is called an incomplete pass. A play is stopped when the player’s knees touch the ground either because of a tackle by a defensive player, a fall, or loss of forward momentum. When a play is over, an official blows a whistle. Normally, teams try to cover the 10 yards in 3 plays or less. If they don't make 10 yards in 3 plays, they use the 4th down to kick the ball toward the other team. The ball is not placed on the ground and kicked as it is in a kickoff. Instead, the ball is snapped back to the kicker who kicks the ball. This is called punting. Teams don't have to punt on 4th down. Sometimes, if the distance to complete the 10 yards is very short, or if a team is far behind in the score, they will elect to go for it on 4th down to try to complete the 10 yards with another play. If they fail to make it on 4th down, the ball is turned over to the opposing team on downs where the last attempt ended. On 4th down, if they are close enough to the defense's goal posts, the offense may also elect to kick a field goal. If the field goal misses, the ball is turned over to the other team with their starting location where at where the ball was before the field goal attempt. If a team succeeds in advancing 10 yards or more, they get a first down. That is, they get a new set of 4 downs to make another 10 yards.
Scoring
The object of the game is to score more points than the opposing team. A touchdown is worth 6 points. After a touchdown, the team that scored can attempt to kick the ball through the goal posts to get extra points. The team that scored the touchdown has the option of trying to get the ball into the opponent's end zone again in by kicking, passing, or running the ball in for extra points. The offense will receive 3 points for the kick, 2 points pass and 1 point if they run it in. If an offensive player is stopped in his own end zone, the defense scores a safety, which is worth 2 points. This rarely happens. After a safety, the offense must kick the ball to the other team with a free kick where the kicker kicks the ball from his own 35 yard line. It's called a free kick because the kicker may not be tackled.
Player Positions
Each team has 12 players on the field. Before a play starts, the offensive players meet in a huddle to plan the execution of a chosen play. Plays are normally selected by the coaching staff and play selection is communicated to the offense through signals to the to the quarterback, or by the use of a runner, who in turn then tells the other players. The defensive players might also huddle to select their own strategy for thwarting the next offensive play. Both teams then come up to the line of scrimmage – an imaginary line drawn from one side of the field to the other through the tip of the football closest to the defense. Each team must stay on their side of the line of scrimmage until the play starts.
Offence
The offensive team typically has a quarterback; two additional players behind the quarterback often called the fullback and the running back; five players in a line in front of the quarterback called the offensive line; and three receivers off to either side of the offensive line that are called tight ends and wide receivers. The tight ends are located close to the offensive line; the wide receivers are further away. The centre player of the five linemen on the offensive line is the centre and that player snaps the ball to the quarterback.
Defense
The defensive team typically has four linemen in front, four linebackers behind the lineman, and four defensive backs, called cornerbacks and safeties who are positioned further back or off to the sides of the field.
The Plays
The offensive linemen all put a hand on the ground, except for the centre, who puts both hands on the ball. The quarterback stands behind the centre with his hands between the centre's legs or further back in shotgun position to receive the ball. The quarterback calls out a series of signals. Only the offensive players know which signal starts the play; the defense has to wait to see the play start before they can react. Once the secret signal is given, the play starts when the centre snaps the ball to the quarterback. The offense has a maximum of 20 seconds from the end of the previous play to start the next play unless a time-out has been called.
Passing Plays
In a pass play, the quarterback takes a few steps back, waits for an offensive player to get open, and throws the ball to that person. That pass receiver can be any offensive player other than a lineman. During a pass play, the defensive front four rush the quarterback hoping to either make him throw the ball early, or perhaps even sack him by tackling him before he throws the ball. The offensive linemen try to prevent this by blocking the defensive linemen. Offensive linemen are not allowed to hold a jersey of an opposing player with their hands while blocking, but defensive players are permitted to use their hands in this way. The defensive backs cover the receivers to try to stop the receivers from catching the ball. They do this by either running with them in man-to-man coverage or by covering any receivers in their assigned part of the field in zone coverage. Sometimes the defensive team blitzes by sending one or more defensive backs after the quarterback. Blitzing can be risky because it can leave a receiver open – but that won't matter if they can sack the quarterback to end the play. If the pass is not caught before it touches the ground, it is ruled an incomplete pass and the ball returns to the original line of scrimmage. If a pass is caught or picked off by a defensive player, it is ruled an interception and the ball is turned over to the other team.
Rushing Plays
In a rushing play, the quarterback hands the ball off to a runningback or, sometimes, the fullback, and that person runs with the ball. The offensive linemen try to open holes in the defensive line for the rusher to run through by blocking the defensive linemen. If the rusher fumbles by losing the ball before the play is over, there is a mad scramble while everyone tries to pounce on the ball. If a defensive player recovers the fumble, the ball is turned over to the other team.
Penalties
The people in the striped shirts are the officials. They carry out various tasks such as raising their arms to signal a touchdown or field goal, deciding if a pass was caught in bounds or out-of-bounds, placing the ball on the line of scrimmage for the next play, measuring to see if 10 yards have been covered, and assessing penalties for rule infractions. To call a penalty, an official throws a yellow penalty marker or flag, from his pocket to the ground. The following are common penalty calls:
- Illegal Procedure: an offensive linemen moved before the play started. Illegal procedure may also be called if the quarterback was past the line of scrimmage when the pass was thrown. This is a 5-yard penalty.
- Ineligible Receiver Down-field: an offensive lineman was too far advanced past the line of scrimmage when the quarterback threw a pass. This is a 5-yard penalty.
- Delay of Game: the offensive team took more than 20 seconds to start the play. This is 5-yard penalty.
- Grounding the Ball: the quarterback threw the ball away instead toward a possible receiver to avoid being sacked. This is a 5-yard penalty and loss of down.
- Off-side: a defensive player moved across the line of scrimmage and either made contact with an offensive player or failed to get back before the play started. This is a 5- yard penalty.
- Holding: hands were used by an offensive player while blocking. This is a 10-yard penalty.
- Clipping, Illegal Block or Blocking a Player from Behind: this type of contact is inappropriate and can hurt a player who doesn't know the hit is coming. This is a 15- yard penalty.
- Pass Interference: grabbing or tackling the pass receiver while the pass is in the air. The defender must wait until the ball arrives before attempting to tackle the receiver. However, the defender can try the catch the ball and may collide with the receiver as they both try to make the catch. If there is interference, the penalty is 15-yards (or to the point of interference if that's less) and a first down is granted even if the ten yards has not been made.
- Unnecessary Roughness, Roughing the Passer, Roughing the Kicker: tackling or hitting a player who no longer has the ball or after the play is over. This is a 15-yard penalty.
- Facemask: grabbing the front of a player's helmet during a tackle. 15 yards if the contact was flagrantly intentional; 5 yards if it was incidental.
- Unsportsman-like Conduct: gesturing, posturing, cursing, taunting, touchdown celebrations, or insults. 15-yards.
After a penalty is called, the other team can sometimes accept or decline the penalty depending the type of penalty called. When a penalty is assessed, the ball is brought back to the original line of scrimmage and the penalty is marched off from there. The down is then repeated unless the penalty includes loss of down. That is, the play with the penalty does not count as one of the 4 allowed to get 10 yards. Thus, if the team with the penalty did poorly on the play, the other team may want to turn down the penalty and accept the play as it was. If both teams get a penalty on the same play, the play is repeated from the original line of scrimmage. The maximum penalty is half the distance to the goal line even if a larger penalty would otherwise be assessed.
The Clock
The last three minutes of a half can take a long time to play. Throughout the game, the clock is stopped whenever there is an incomplete pass or the player with the ball runs out-of-bounds. The clock is stopped temporarily when there's a first down so the officials can move the chains at the side of the field that are used to measure the 10 yards. And each team has 3 time-outs they can call per half to stop play for a couple of minutes. In the last 2 minutes, the offense uses incomplete passes and running out-of-bounds just to stop the clock. There is a three-minute warning signaled by the officials at the end of each half, during which the play clock will be stopped for time-outs, injuries, penalties and scoring.
NOTE: Some leagues may adopt shorter times per quarter.
