American Football is one very physical type of sport. Therefore, if one wants to avoid the risk of injuries when playing the game, it is crucial that they wear the proper sort of protective gear. In America football the fields are 100yards long and 53 1/3 yards wide. The goal posts in American football are placed at the back of the end zone.
American football teams have 11 players. This means that the typical American offensive setup has 5 linesmen beginning with the Center who stands at the front of the Quarterback and who is responsible for handing the ball to him. There are Guards to the right and left of the Center, as well as an Offensive Tackle next to each Guard. The task of the offensive line is to jointly protect the Quarterback from players in the opposing team's defense. In case a kick returner thinks that he won’t be able to advance the ball following recovery, he could signal for a fair catch and still be immune from contact.
There are generally 4 linesmen on the defense, even though this could change depending upon the defensive scheme the team is using. There will be 2 Defensive Tackles in the middle (1 if the team only uses 3 lineman) who are normally responsible for getting around the Center and the Guards. There will be the Defensive End on both sides on the outside of the line, who will attempt to get around the Offensive Tackles. The outcome of the game is normally determined on the basis of which team wins the battle at the line, or even "in the trenches".