The sport is typically known as simply "football" in the countries where it originated, regardless of the specific variety. In Europe the … See more

• American football is the most common and widely known of these sports. It was originally more closely related to rugby, until various rule changes created by Camp were implemented in 1880, such as the system of downs, and the two sports diverged … See more

According to 2017 study on brains of deceased gridiron football players, 99% of tested brains of NFL players, 88% of CFL players, 64% of semi-professional players, 91% of college football players, and 21% of high school football players had various stages of See more

1. ^ "Gridiron football". Encyclopædia Britannica. Retrieved October 20, 2010.
2. ^ Jack Brimberg and William Hurley (2006). "Strategic … See more

The sport developed from informal games played in North America during the 19th century. Early games had a variety of local rules and were generally similar to modern rugby union See more

This is a minimal description of the game in general, with elements common to all or almost all variants of the game. For more specific rules, see each code's individual articles.
Prior to the start of a game, a coin toss determines which … See more

• American football in the United States
• Comparison of American and Canadian football
• Concussions in American football
• Football (word) See more