Association Football.

Association football, known as football or soccer, is a team sport played between two teams of eleven players, and is widely considered to be the most popular sport in the world. It is a football variant played on a rectangular grass or artificial turf field, with a goal at each of the short ends. The object of the game is to score by scoring the ball into the opposing goal. In general play, the goalkeepers are the only players allowed to use their hands or arms to propel the ball, the rest of the team usually use their feet to kick the ball into position, occasionally using their head to intercept a ball in midair. The team that scores the most goals by the end of the match wins. If the score is tied at the end of the game, either a draw is declared or the game goes into extra time and/or a penalty shootout, depending on the format of the competition.

The modern game was codified in England following the formation of The Football Association, whose 1863 Laws of the Game created the foundations for the way the sport is played today. Football is governed internationally by the Federation Internationale de Football Association (International Federation of Association Football), known by the acronym FIFA. The most prestigious international football competition is the FIFA World Cup, held every four years. This event, the most widely viewed in the world, boasts an audience twice that of the Summer Olympic Games.

Overview.

In typical game play, players attempt to create goal scoring opportunities through individual control of the ball, such as by dribbling, passing the ball to a team-mate, 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. Football is generally a free-flowing game, with play stopping only when the ball has left the field of play or when play is stopped by the referee. After a stoppage, play recommences with a specified restart.

At a professional level, most matches produce only a few goals. For example, the 2005-06 season of the English Premier League produced an average of 2.48 goals per match. The Laws of the Game do not specify any player positions other than goalkeeper, but a number of specialised roles have evolved. Broadly, these include three main categories: strikers, or forwards, whose main task is to score goals; defenders, who specialise in preventing their opponents from scoring; and midfielders, who dispossess the opposition and keep possession of the ball in order to pass it to the forwards on their team. Players in these positions are referred to as outfield players, in order to discern them from the single goalkeeper. These positions are further subdivided according to the area of the field in which the player spends most time. For example, there are central defenders, and left and right midfielders. The ten outfield players may be arranged in any combination. The number of players in each position determines the style of the team's play; more forwards and fewer defenders creates a more aggressive and offensive-minded game, while the reverse creates a slower, more defensive style of play. While players typically spend most of the game in a specific position, there are few restrictions on player movement, and players can switch positions at any time. The layout of a team's players is known as a formation. Defining the team's formation and tactics is usually the prerogative of the team's manager.

Pitch.

The length of the pitch for international adult matches is in the range 100–110 m (110–120 yd) and the width is in the range 64–75 m (70–80 yd). Fields for non-international matches may be 91–120 m (100–130 yd) length and 45–91 m (50–101 yd) in width, provided that the pitch does not become square. The longer boundary lines are touchlines or sidelines, while the shorter boundaries (on which the goals are placed) are goal lines. A rectangular goal is positioned at the middle of each goal line. The inner edges of the vertical goal posts must be 7.3 m (8 yd) apart, and the lower edge of the horizontal crossbar supported by the goal posts must be 2.44 m (8 ft) above the ground. Nets are usually placed behind the goal, but are not required by the Laws.

In front of each goal is an area known as the penalty area. This area is marked by the goal line, two lines starting on the goal line 16.5 m (18 yd) from the goalposts and extending 16.5 m (18 yd) into the pitch perpendicular to the goal line, and a line joining them. This area has a number of functions, the most prominent being to mark where the goalkeeper may handle the ball and where a penalty foul by a member of the defending team becomes punishable by a penalty kick. Other markings define the position of the ball or players at kick-offs, goal kicks, penalty kicks and corner kicks.