American football is a sport played by two teams of eleven players on a rectangular field 120 yards long by 53.33 yards wide with goalposts at each end. The offense attempts to advance an oval ball down the field by running with or passing it. They must advance it at least ten yards in four downs to receive a new set of four downs and continue the drive; if not, they turn over the football to the opposing team. Most points are scored by advancing the ball into the opposing team's end zone for a touchdown or kicking the ball through the opponent's goalposts for a field goal. The team with the most points at the end of a game wins.
source:wikipedia\Image by: Eddie Donovan