1 The pitch. Length: 100–130 yds (90 m–120 m). Width: 50–100 yds (45 m–90 m). The two long lines are called touchlines, the two short lines are called goal lines. The pitch is divided by a halfway line, with a centre point where the ‘kick-off’ occurs to begin the match. At each goal, there is a 6-yard box (5.5 m) known as the goal area. Outside that, there is an 18-yard box (16.5 m) known as the penalty area. A penalty spot is drawn 12 yards (11 m) in front of the goalposts. The goalposts are 8 yards (7.32 m) apart and 8ft (2.44 m) high.

      2 The ball. Circumference: between 27 and 28 inches (68–70 cm). Weight: between 14 and 16 oz (410–450 g).

      3 The teams. No more than eleven players can be fielded by each team, including the goalkeeper. Depending on the competition, between three and seven substitutes can be used. In addition, any player can change places with the goalkeeper provided that the referee is told and the change occurs while play has stopped.

      4 Clothing. Players wear football shirts, shorts, shinguards under long socks and football boots. Goalkeepers wear different-coloured kits.

      5 The referee. All decisions by the referee are final. Powers include the ability to give a verbal warning, a more serious yellow card warning, or a red card, which results in immediate sending off. A second yellow card is equivalent to a red. The referee also acts as timekeeper for the match and controls any restarts after stopped play.

      6 Assistant referees (linesmen). These indicate with a raised flag when a ball has crossed the lines and gone out of play, and let the referee know which side is to take the corner, goal kick, or throw-in. They also raise their flags to indicate when a player may be penalised for being in an offside position.

      7 Duration. Two halves of forty-five minutes, with a half-time interval of no more than fifteen minutes.

      8 Starting. Whichever team wins a coin-toss kicks off and begins play. The ball returns to the centre spot after a goal and at the start of the second half. All opposing players must be in their own half at kick-off – at least ten yards (9.15 m) from the ball.

      9 In and out. The ball is out of play when it crosses any of the touchlines or goal lines, or if play has been stopped by the referee. It is in play at all other times.

      10 Scoring. The whole ball has to pass over the goal line. If a member of the defending team knocks it in by accident, it is an ‘own goal’ and still valid. Whoever scores the most goals wins.

      11 Offside. The offside rule is designed to stop players hanging around the goal of their opponents, waiting for a long ball to come to them. A player is given offside if the ball is passed to him while he is nearer to the goal than the ball and the second-last defender. Note that players are allowed to sit on the goal line if they want, but the ball cannot come to them without offside being called by the referee. An ‘offside trap’ is when defenders deliberately move up the field to leave a forward player in a position where he cannot take the ball without being called offside. It is not an offside offence if the ball comes to a player from a throw-in, a goal kick or a corner kick.

      12 Fouls. Direct and indirect free kicks can be given to the opposing team if the referee judges a foul has been committed. The kick is taken from where the foul occurred, so if it is close to the opponent’s goal, the game can easily hinge on the outcome. Fouls can range from touching the ball with the hands to kicking an opponent. In addition, the player can be cautioned or sent off depending on the offence.

      13 Free kicks. Direct free kicks can be a shot at goal if the spot is close enough, so are given for more serious fouls. The ball is stationary when kicked. Opposing players are not allowed closer than ten yards (9.15 m), which has come to mean in practice that the opposing team put a wall of players ten yards from the spot to obscure the kicker’s vision. Indirect free kicks cannot be directly at goal, but must first be passed to another player.

      14 Penalties. These are awarded for the same offences as direct free kicks – if the offence happens inside the penalty area of the opposing team. This is to prevent what are known as ‘professional fouls’, where an attacker is brought down deliberately to stop him scoring. The goalkeeper must remain on his goal line between the posts until the ball has been kicked. Other players must be outside the penalty area and at least ten yards from the penalty spot – that’s why there’s an arc on the penalty area. The penalty must be a single strike at the goal. As long as it goes in, it can hit the posts and/or goalkeeper as well. In the normal run of play, a penalty kick that rebounds off the keeper is back in play and can be struck again. In a penalty shootout, this does not apply and there is only one chance to score.

      15 Throw-ins. A player must face inwards to the field and have both feet on the ground, on or behind the touchline. Both hands must be used and the ball must be delivered from behind the head. The thrower must pass the ball to another player before he can touch it again.

      16 Goal kicks. These are given when the opposing team kick the ball over the opposing goal line, after a missed shot at goal, for example. The goal kick is taken from anywhere within the goal area and the ball must pass out of the penalty area before another player can touch it.

      17 Corner kicks. These are given when a member of the defending team knocks the ball over his own goal line. The goalkeeper may do this in the process of saving a goal, for example, or a defender may do it quite deliberately to prevent a shot reaching goal. Many goals are scored from corner kicks, so the tension is always high when one is given.