American football is the most popular sport in the United States, enthralling millions of people. However, in Europe, this sport has only gained popularity in the last decade. Let's familiarize ourselves with the rules and mechanics of American football. Important Notes and Terms To better understand the fundamentals of American football rules, keep in mind a few things: In American football, everything is measured in yards. 1 yard = 91.44 cm. To simplify the game's math, it's common to round and equate one yard to 90 centimeters. TD – touchdown – carrying the ball into the opponent's end zone, earning points. NFL – National...