Canadian football is very similar to American football except for slight rule differences. Developed during the 19th century, its origins come from rugby football and are influenced by American football. Today, it's played in Canada by high schools, colleges, universities, and nine professional teams that are the Canadian Football League (CFL). The Canadian football field is 100 meters long and 59 meters wide, larger than its American version. The team consists of 12 players, including one captain. A regulated number of American-born players can play on the Canadian teams. Teams play for four, 15 minute periods which add up to one hour or 60 minutes of playing time. Scoring in Canadian football is the same as in American football, except that the Canadian field has a dead-line 25 yards behind each goal line. On a kickoff, the receiving team must advance the ball out of the area between the dead-line and the goal line. If it fails, the kicking team scores 1 point, called a single. The same rule applies to a punt.

Jonathan Zelyakovsky -- 2003