The game is played on a 120 yard long field. Ten yard sections on each end of the field are the designated scoring areas known as the end zones. Between the end zones, in the 100 yard section, is where the bulk of the game is played. The field is slightly over fifty yards in width. Each team has eleven men on the field at all times and different players are assigned to a certain strategic position on the team, be it on offense or defense. Once a team has possession of the ball, its offense has four opportunities to move the ball at least ten yards.
Moving the ball is done in two different ways: running forward with the ball or passing the ball forward to a member of the same team. A player is stopped by the defense by tackling to the ground. Upon moving the ball ten yards, the team achieves what is called a first down. Getting a first down resets the set of downs and gives the team another four opportunities to move the ball ten yards.
One scoring play in football is called a touchdown, where the team crosses into the end zone with the ball either by run or pass. A touchdown is worth six points and the team also gets a chance to add on one or two points after the play. If a team falls short of the end zone, they have the option of kicking a field goal. If the designated kicker can boot the ball through the eighteen and a half foot wide goalposts, the play is worth three points. The defense's primary assignment is trying to stop the offense, but they also have an opportunity to score. They can intercept a pass and run back to the opposite end zone. Offensive possession is also lost on the fumble, which is when a ball carrier drops the ball and the defense recovers.
Football is played on all levels in America and is popular in all regions, with its most watched divisions being the collegiate level (NCAA) and the professional level (NFL). The most popular single game is the NFL championship, known as the Super Bowl. It is the most watched television event in the United States every year. Football continues to expand and grow, with leagues and exhibition games being played in several countries.