Normally when we think of football we think of passing or running the ball, and defending against passes and runs. However, there are other important parts of the game. At the beginning of each half and after each score, one team kicks off and the other receives a kick. Each time an offense is stopped they punt the ball to the other side. After each touchdown there is a kick for an extra point. And frequently there are kicks for field goals. There are special players to handle each of these actions. The special players are members of what are called the special teams.
A football team will typically carry three special teams specialists on their roster. These three guys are a kicker, who will kick off the ball and attempt field goals and extra points. A punter, who punts the ball when the offense is stopped. And a long snapper, an extra center who specializes in snapping the ball 20 feet back be kicked or punted. Sometimes a team will have an existing player, for example a tight end, who can also long snap. Sometimes a team will carry an extra guy on the roster just because he is so good at tackling after a kickoff or a punt, or catching and returning kicks and punts.
On punts there will be two guys on the punting team lined up wide, like wide receivers. These two guys are called the gunners. They are the only players on the kicking team allowed to start running down field as soon as the ball is snapped. Everyone else on the kicking team must wait until the ball is kicked. The gunner's job is to try to get down the field as fast as the kicked ball and tackle whoever catches it. In the best case, they get there just before the ball and make the other team afraid to try to catch it. When a team lines up to punt, the other team lines up in a defense that is designed to also receive a punt. There will be one guy lined up about 40 yards back; he is the receiver, the player designated to catch the punt. There will also be a few guys lined up on the gunners. If the defense lines up two defenders on each gunner, then they are hoping to slow the gunners down, catch the punt, and try to run the punt back for a long gain or even a touchdown. If there is only one defender lined up on each gunner, then the receiving team has extra guys rushing the punter and they hope to block the punt.
On kickoffs, there's a special kind of kickoff called an on-side kick. If you kick the ball, after the ball has travelled 10 yards it is up for grabs. There's a group of players called the "hands" team that each team puts on the field if an onside kick is anticipated. These are tight ends, receivers, safeties, and cornerbacks - players who are accustomed to catching the ball.
There are seven officials on the field during a game. By rule the officials are like part of the field, so if your receiver runs into one, too bad for you. The seven officials are:
The Referee. Responsible for general oversight and control of game. This is the guy who signals and talks to the TV crowd. He's the final authority for rule interpretations. He takes a position in the backfield 10 to 12 yards behind line of scrimmage and focuses mostly on the quarterback or kicker.
The Umpire. He lines up approximately four to five yards downfield. He watches the linemen for false starts and illegal blocks.
The Linesman. He lines up on the ball and watches for offsides and encroachment, and rules on sideline plays on his side such as pass receiver or runner in or out of bounds. He also watches receivers on his side for at least the first seven yards checking for holding and illegal blocks.
The Line Judge. He lines up on the ball opposite the Linesman. Along with the Linesman he is responsible for offsides and encroachment, and rules on sideline plays on his side such as pass receiver or runner in or out of bounds. He also watches receivers on his side for at least the first seven yards checking for holding and illegal blocks. The Line Judge rules whether the passer is behind the line of scrimmage when pass is made. The Line Judge maintains a clock in case the stadium clock fails.
The Field Judge. He operates on same side of the field as the Line Judge, 20 yards deep. He watches the end or back, checking for blocks, holding, and illegal use of hands. He also watches the pass receiver or runner for out of bounds, legal catch and pass interference. He's one of the two refs who rules on field goal attempts.
The Side Judge. He operates on same side of the field as the Linesman, 20 yards deep. He watches the end or back, checking for blocks, holding, and illegal use of hands. He also watches the pass receiver or runner for out of bounds, legal catch and pass interference. He's one of the two refs who rules on field goal attempts.
The Back Judge. He takes a position 25 yards downfield on the tight end’s side of field. He watches the tight end, checking for blocks, holding, and illegal use of hands. He also calls pass interference, fair catch infractions, and clipping on kick returns. He stays with ball on punts. Together with the Field Judge he rules whether or not field goals and conversions are successful.