Football is a team sport in which players compete to get the ball into their opponent’s end zone. The game is played on a field up to 120 yards long, and teams consist of 11 players from each side. A player can score points by catching, running with or throwing the ball. Getting the ball over the goal line wins the game, but points can also be scored by passing or running the ball into the end zone.
The game begins with the “snap,” when a player called the center passes or snaps the ball between his legs to the quarterback, holder, or punter. The quarterback then calls out a play in code, and the players in front of him—the offensive linemen—hand or toss the ball upfield. The running backs then hand off the ball to the wide receivers, or run with it themselves. The wide receivers line up near the sides of the field and specialize in catching passes.
After the ball is snapped, each team gets four attempts to advance the ball 10 yards downfield, called a first down. If the offensive team cannot reach a first down in four tries, it must punt the ball to the defensive team. The offensive team then has a new set of four downs to advance the ball to the next first down.
The goal of the defense is to stop the offensive team from advancing by tackling the ball-carrier or by intercepting passing plays. A tackle is completed when a player brings the other team’s ball carrier to the ground with his feet or hands. Attempting to tackle a player behind the line of scrimmage (which is marked on TV broadcasts as a yellow line) is a penalty and may result in the defensive team taking over possession of the ball.
If a team is not close enough to the opposing end zone on a touchdown, it can opt to try for a field goal. The team must kick the ball over a crossbar and through the uprights for 3 points (a field goal), or run or pass the ball into the end zone for 2 points (a touchdown).
In addition to the seventeen laws of football, various IFAB decisions and directives regulate the game. These rules are generally the same for all levels of competition. However, some exceptions are made for younger or senior players.