Football is a sport played between two teams of eleven players with a spherical ball. It is played by 250 million players in over 150 countries, making it the world's most popular sport. The game is played on a rectangular field with a goal at each end. The object of the game is to score by getting the ball into the opposing goal.
The Laws of the Game were originally codified in England by The Football Association in 1863. Association football is governed internationally by the International Federation of Association Football (FIFA; French: Fédération Internationale de Football Association), which organises World Cups for both men and women every four years.
In game play, players attempt to create goal–scoring opportunities through individual control of the ball, such as by dribbling, passing the ball to a teammate, and by taking shots at the goal, which is guarded by the opposing goalkeeper. Opposing players may try to regain control of the ball by intercepting a pass or through tackling the opponent in possession of the ball; however, physical contact between opponents is restricted.
Variants of football have been codified for reduced–sized teams (i.e. five–a–side football) play in non–field environments (i.e. beach soccer, indoor soccer, and futsal) and for teams with disabilities (i.e. paraolympic association football).
One of the attractions of football is that a casual game can be played with only minimal equipment – a basic game can be played on almost any open area of reasonable size with just a ball and items to mark the positions of two sets of goalposts. Such games can often have team sizes that vary considerably from 11–a–side, use a limited and/or modified subset of the official rules, and are likely to be self–officiated by the players.