Both teams must have 11 players on the field at a time. There are three phases of a game, offense, defense, and special teams. Offense, when you score most of your points, is when you have the ball. Defense is when the other team has the ball. If you have more than 11 players on the field, then it is a penalty. A penalty is when a team breaks a rule during a play. The field you play on is 100 yards long and about 53 yards across. A player must wear a helmet, shoulder pads, pads on his thighs and knees, and a tailbone pad. There are seven officials on the field during a professional game. The officials watch the game and call a penalty on a player if they break a rule. Football seems complicated, but if you know the game it is pretty