Duration of the match
The match officially lasts 90 minutes, split into two 45-minute halves with a half-time interval of no longer than 15 minutes.
In the knock-out stages of competitions, extra-time is used if there is no winner after 90 minutes. This extra period is 30 minutes, split into two 15 minute halves. If extra-time does not find a winner, then a penalty shoot-out takes place, where five players from each team are selected and alternate shots on goal from the penalty spot against the opposition goalkeeper. In that instance, the team with the most successful penalties is declared the winner. If they are still tied then they will move on to sudden-death penalties, where each team will take one penalty until one of the two sides has scored move than the other after the side amount of spot kicks.
Start and restart of play
A coin toss takes place just before the game starts, the winner of which will get the choice of choosing which end to attack or whether to kick-off. Should they choose to kick-off then the other captain will be allowed elect which end to attack in the first half. Should the winner decide to choose which end to attack then the loser can choose whether to kick-off in the first or second half.
The kick-off is also used after a goal has been scored, the task befalling the team who has conceded, and for both halves of extra-time.
At the kick-off, players from each side must all be in their half of the field. The actual kick-off takes place on the centre spot in the centre circle. The player who kicks off cannot touch it again until another player has made contact.
Scoring
A team can only score if the whole ball crosses the goal line between the goalposts. The winner is the team who scores more goals, except in a competition where the 'away goals' rule applies. The 'away goals' rule means that, if a team scores a goal away from their home stadium, the goal counts extra (therefore, a 1-1 scoreline would mean the away team wins).
Offside
The perennial problem for newcomers to football is understanding the offside rule. This is made somewhat harder by the fact there are two elements to offsides in football; being in an offside position, and committing an offside offence.
To be in an offside position is to be closer to the opponent's goal than the last opposition outfield player (therefore excluding the goalkeeper) and the ball. However, to commit an offside offence is to have the ball played forward towards you while in that position. As such, you can be in an offside position and not commit an offside offence.