American football
Football games last for a total of 60 minutes in professional and college play and are divided into two-halves of 30 minutes and four-quarters of 15 minutes. High school football games are 48 minutes in length with two-halves of 24 minutes and four-quarters of 12 minutes. The two-halves are separated by a halftime period, and the first and third quarters are also followed by a short break. Prior to the start of the game, the referee and team captains for each team meet at midfield for a coin toss. The visiting team is allowed to call 'heads' or 'tails'; the winner of the toss is allowed to decide between choosing whether to receive or kick off the ball or choosing which goal they want to defend, but they can also defer their choice until the second half. The losing team, unless the winning team decides to defer, is allowed to choose the option the winning team did not select, and receives the option to receive, kick, or select a goal to defend to begin the second half. Most teams choose to receive or defer, because choosing to kick the ball to start the game would allow the other team to choose which goal to defend. Teams switch goals following the first and third quarters. If a down is in progress when a quarter ends, play continues until the down is completed.
Delay of game
The foul known as "delay of game" in American football is called "time count" in Canada. It is generally identical to the American foul, with two important exceptions. First, Canadian football only allows the offensive team 20 seconds from the referee's signal to put the ball in play, as opposed to the longer periods allowed in the American code. Second, the penalty, which is identical to that in the American code during most of the game, including convert attempts at any time, is dramatically different after the Canadian code's three-minute warning near the end of each half. After the three-minute warning, the base penalty becomes loss of down on first or second down, instead of the regular 5 yards. On third down (the final down that the offensive side has to gain a first down), the penalty becomes 10 yards with the down repeated. The referee also has the right to give possession to the defensive team if he deems repeated time count violations on third down to be deliberate.