
Step 1: The Object of the Game
* In the game of American football, two teams compete to score points by moving a ball into the end zones of their opponents—either passing the ball from one player outside the end zone to another who's inside, running the ball from the playing field into the end zone, or sometimes kicking the ball through an end zone's goal posts. But more on scoring later.
1. Each team has 11 players on the field.
* Smaller teams or leisure players may compete with eight or fewer participants.
2. The team with the ball at any given time is called the offense.
3. The other team, which tries to stop the offensive advance and "defend" its end zone, is called the defense.
Step 2: The Set Up
1. Regulation football fields (minus the end zones) are 100 yards long. Each end zone contains a goal post and is 10 yards long. Yards are measured from each respective end zone's goal line, beginning with 1, until yard markers meet in the middle at the 50 yard line.
2. Though all yards are measured with "hash marks" or white lines on the sidelines, plus a line extending across the width of the field every five yards. Only every 10th yard line (10, 20, 30, etc.) is labeled with a numeral.
Play time:
1. The length of a football game is divided between two halves, each with two quarters. In professional football (NFL), along with college (NCAA) and arena football, each quarter in a game is 15 minutes long with a 12-minute half time between the second and third quarters. High school teams, however, play 12-minute quarters in a 48-minute game. Participants in amateur leagues or friendly games may shorten these periods.
2. When there are two minutes of play remaining before the end of each half, respectively, officials signal for a "two-minute warning." This stops the clock and serves as a free timeout for the teams.
3. An additional overtime play period is added if the teams are tied at the close of the fourth quarter.
4. To stop the clock, teams are allotted a number of timeouts (three per half in the NFL). In addition, some plays, such as running the ball out of bounds or scoring, can stop the clock (Arena Football has exceptions to this rule).
Kickoff:
1. At the beginning of each half, and after every time a team scores, that team kicks the ball at their own 30-yard line to the receiving team. The receiving team, or offense, can then run the ball as far as they can toward the defensive team. The play ends either when the player who caught the ball is stopped by the defense or if he scores.
2. It is illegal to kick the ball outside the lines of the playing field, so consequently, when that happens, the receiving team automatically gets to start their possession on the field where the ball went out of bounds or 30 yards from where it was kicked off.
3. If the ball is kicked into the receiving team's end zone, the receiver can either run the ball or go down on one knee. When he does this, it's called a touchback. It means the play is over and the ball will be placed at the 20-yard line for the next series of plays. A touchback is also the result of kicking the ball out of bounds in the end zone.
Step 3: The Players
* It's a lot easier to understand how points are scored once you get to know the players and their positions. The lineup of these positions is not static and coaches often will change the numbers of players in certain positions to achieve a certain outcome. But here is a general outline of a team's lineup:
The offense
1. Quarterback: Often at the center of attention on a team is the quarterback, whose job it is to call plays for the offense. He's also the play maker because he's the one who must either pass/throw the ball to another player after it's snapped to him, hand it off to a fellow player or hang onto the ball and run it up the field himself.
2. Center: Aptly named, the center is the player who crouches in front of the quarterback before a play and then snaps the ball back through his legs to his quarterback.
3. Running back: A running back is typically the one who is handed the ball by the quarterback if a running play is called, but also can be called upon to block and throw or receive passes. He can be either a fullback or a halfback (AKA tailback), depending on the type of offense being played, and is extremely versatile.
4. Guards: The guards (right and left) flank the center player and their job is to block (not tackle) their defensive counterparts in order to keep the ball moving forward.
5. Tackles: The tackles (right and left) line up on the outside of the respective guards and join them in their efforts to protect the ball and keep defenders at bay.
6. Tight end: This player can double as a receiver or blocker, depending on the play call, and may line up on either end of the offensive line.
7. Wide receivers: The fast players are usually sent down the field to catch the football when a pass is called for by the quarterback. It's their job to get on a good running route and stay open to catch the ball. On running plays, they may help with blocking duties.
Step 4: Scoring
Touchdown
1. A touchdown is worth six points. It is the result of the offense getting the ball into their opponents' end zone—either by way of a caught pass in the end zone or a run into the end zone.
2. In order for a touchdown to count, a player must be inbounds, be in full possession of the ball and the ball must break the plane of the goal line.
Extra point(s)
1. After a touchdown, the team with the ball has the opportunity to kick it through the goal posts from the 2-yard line for an additional point.
2. Or they can opt for a two-point conversion, which is scored the same way as a touchdown, also set up at the 2-yard line.
3. Because the two-point conversion is riskier, most teams only use it at a crucial point in the game and/or if a successful conversion will put them in the lead. For instance, if the clock is winding down and the touchdown-scoring team is trailing by two points, the coach is likely to call for a two-point conversion. If the team is successful, it will at least tie the game before time runs or at most put players in the position of winning (as long as they can keep their opponents from scoring on the next possession).
4. Touchdown-scoring teams that are in the lead, or are one or more points behind with ample time on the lock, will rarely "go for two" because a kick attempt is considered the safer move.
Field goal
1. A field goal is worth three points. It is the result of the offensive team's kicker kicking the ball between the goal posts of the opponents' end zone.
2. This is usually done when the offense is close enough to the end zone for its kicker to be in range (typically within 40 or so yards) and either a touchdown is not needed to secure a victory or the players have failed to convert a third down into a first down.
Safety
1. A safety is worth two points. It is the result of a defensive player tackling an offensive player who's in possession of the ball in his own end zone.
2. The scoring team then gains possession of the ball.
Step 5: Penalties
1. Despite how it appears sometimes, football is not a free-for-all. There are a number of penalties a team can incur, each of which almost always result in a loss of yardage for the offending team (typically 5-10 yards if they aren't personal fouls, which cost the team even more yardage).
2. From time to time, the opposing team may opt to decline a penalty and its benefits when the outcome of the play itself is more desirable than the penalty's consequences (i.e. if offsides is called on the defense during a long pass play, but the result of the penalty for the offense is fewer yards gained than the result of the completed pass, the offense will decline the penalty and thus start a new series of downs at the place where the receiver ended the play).
3. Teams can choose to "challenge" a penalty.
* The number of challenges a team's coach is allowed to make per game differs depending on the level of play: one in collegiate competition and two in professional competition (if the first two penalties are overturned as the result of an NFL coach's challenge, then a third challenge is allowed).
* A college coach makes a challenge during a timeout. An NFL coach, however, may challenge between plays and is only charged with a timeout if the ruling is not reversed.
* A "booth review" of a penalty can be called for by an off-field official at any point during the game. In professional play, a coach may throw his challenge flag at any point, except after the two-minute warning in each half.
* Officials review the play on the sideline on an instant replay screen.
* Some non-penalty calls can be challenged, as well.
4. When a penalty is committed in a non-amateur game, one or more of the game's officials will pull a yellow flag out of his pocket and throw it on the field as he blows his whistle. This stops the clock and—usually—one of the following general penalties is cited
Step 6: Turnovers
* Staying in possession of the football for as long as possible means more opportunities to score. So players should beware of the following blunders that mean turning the ball over to the other team.
1. Interception: A defensive player may intercept a pass in mid-air between the quarterback and an intended receiver, after which he'll run as far as possible (perhaps even into the end zone) without getting tackled. The offense must then surrender the ball and their field position as the opponents start a set of downs at the location where the ball died, except in the case of defensive touchdown.
2. Fumble: Dropping a football while in play is called a fumble. The player who dropped the ball, or one of his teammates, may recover the fumble. But if a defensive player gets his hands on it first, the football is his and that team takes possession at the location where the ball died, except in the case of defensive touchdown.
3. Downs: If the offense fails to move the ball 10 yards after three downs, it may be forced to punt kick to the other team. (This happens at the location of the last play and, if the kick goes out of bounds, the receiving team must take possession at the yard line where the ball was kicked out.) However, if after three downs the offensive team decides to go for it on the fourth down and misses again, they turn the ball over to the defense at the location of the last play.
4. Missed field goal: No matter where they are on the field or which down they're at when a field goal is attempted, offensive players automatically lose possession if the kicker misses the goal.
5. Safety: When the offensive team has been pushed back into its own end zone by the defense, a defender cannot only earn two points for tackling the offensive player who has the ball, but he wins back immediate possession of the football when the tackled team is forced to punt.
Step 7: Play at Home
* Football needn't be a spectator sport. All you need to enjoy the fun is a few friends and some open space. There are a few different ways to go about organizing your own game.
* No matter which of the following varieties you opt for—touch, flag or tackle—any open space can be the field. Since it's difficult to find 100 yards of play space, not to mention cover it with as few as four players, you will likely need to redefine first down (i.e. a number of completed passes instead of a distance) or eliminate it altogether. It's also a good idea to simplify the player positions to accommodate smaller teams. In addition, many leisure players choose not to kick field goals or extra points because there are most likely no goal posts.
* The important thing to remember when playing with friends is that it's about having fun. There is no right or wrong way to determine how scoring, timing, etc. will play out in your game. Simply get together before "kickoff" and agree on some guidelines.
Touch football
* The major difference between this type of game and the ones you see on TV is that "tackling" is done by a defender merely touching the ball carrier with either one or two hands—hence the one-hand or two-hand touch versions of playing. Any number of participants can play as long as the sizes of the teams are equal. If the number of players isn't even, try appointing a single player as the quarterback for both teams. Touch football is a safe option for young people, especially those who don't have protective gear.
Flag football
* As in touch football, flag football's "tackling" is accomplished in a much different way than organized football: Defenders must grab the flag from a ball carrier's belt to stop the play. In general, flag football has more uniform rules than its one- or two-hand touch counterpart. Of course, games can by played as casually as a touch contest, but there is a United States Flag Football Association with its own rule book.
Tackle football
* Tackle football is essentially good ol' fashioned, no-holds-barred American football, with or without protective equipment. Play at your own risk!




