Everything You need to Know About American football

American football is a game in which there are two teams of eleven players each (that is, eleven players for each team allowed on the field at any one time; there are plenty more waiting on the sidelines, . . . but that's another story).

And speaking of sidelines, here's a look at them, with a regulation football field in between.

You'll notice that, when seen in this diagram version, a football field resembles an old-fashioned board game, like checkers.

And at its most basic, that's pretty much what football is: checkers on grass.

As in checkers, the "pieces" are attempting to move into their opponents' territory. In checkers,the pieces move from box to box. In football, it's line to line. Note the stripes marked across the hundred-yard football field at five-yard intervals. The rule is that a team must move the ball forward a minimum of ten yards in four tries (called 'downs') in order to get another chance to move the ball ten yards in four downs.

AIM

• The purpose of American football is to move the ball towards the opposition's end zone and ultimately into their end zone.
• This is achieved by either running with the ball until tackled, or throwing the ball down field to a team mate.

DOWNS

• Downs are the most fundamental part of NFL play. The offensive team moves the ball forward in sections of at least 10 yards. They have four chances (or downs) to gain those 10 yards. Each time the ball is advanced at least 10 yards within their four chances, another first down is earned, with four more chances to go a further 10 yards.
• If the offensive team fails to move 10 yards within four downs, possession is surrendered. However, the ball is usually punted to the defending team on fourth down.

TIMING

• Four 15 min quarters
• Three time-outs per half for each team
• 12 min half-time
• 15 min sudden-death overtime if scores are tied

SCORING

• A touchdown is worth six points, and is scored when a team crosses the opposition's goal line with the ball, or catches or collects the ball in the end zone.                        
• A Field goal is worth three points. Field goals are usually attempted on fourth down if the kicker is close enough to the end zone to kick the ball through the posts.

• An extra point is earned by kicking the ball through the uprights after a touchdown. The team can go for two points by taking the ball into the end zone again.                
• Two points is awarded to the defensive team for a safety when a member of the offensive team is tackled with the ball in his own end zone.