The term "football" in both American football and rugby can be traced back to their common origins in various forms of football played in England during the 19th century. During this time, different regions and schools in England had their own variations of football, each with its own set of rules.
In rugby, playing time is set at a total of 80 minutes, with two 40- minute half times, compared with four 15-minute quarters for American football. These periods of play are followed by a 12-minute halftime after the first two quarters. The second difference is the total number of players on the field.