page_title: American football
section_title: Offensive unit
hierarchical_section_title: American football / Teams and positions / Offensive unit
caption_attribution_description: Deutsch: Quarterback Jeff Welsh kurz vor dem nächsten Spielzug; davor Center Oliver Beeck bereit zum Snap (Ballübergabe an Quarterback).
context_page_description: American football, referred to as football in the United States and Canada and also known as gridiron, is a team sport played by two teams of eleven players on a rectangular field with goalposts at each end. The offense, the team with possession of the oval-shaped football, attempts to advance down the field by running with the ball or passing it, while the defense, the team without possession of the ball, aims to stop the offense's advance and to take control of the ball for themselves. The offense must advance at least ten yards in four downs or plays; if they fail, they turn over the football to the defense, but if they succeed, they are given a new set of four downs to continue the drive. Points are scored primarily by advancing the ball into the opposing team's end zone for a touchdown or kicking the ball through the opponent's goalposts for a field goal. The team with the most points at the end of a game wins.
  American football evolved in the United States, originating from the sports of soccer and rugby. The first American football match was played on November 6, 1869, between two college teams, Rutgers and Princeton, using rules based on the rules of soccer at the time.
context_section_description: The role of the offensive unit is to advance the football down the field with the ultimate goal of scoring a touchdown.
  The offensive team must line up in a legal formation before they can snap the ball. An offensive formation is considered illegal if there are more than four players in the backfield or fewer than five players numbered 50–79 on the offensive line. Players can line up temporarily in a position whose eligibility is different from what their number permits as long as they report the change immediately to the referee, who then informs the defensive team of the change. Neither team's players, except the center (C), are allowed to line up in or cross the neutral zone until the ball is snapped. Interior offensive linemen are not allowed to move until the snap of the ball.
  The main backfield positions are the quarterback (QB), halfback/tailback (HB/TB) and fullback (FB). The quarterback is the leader of the offense. Either the quarterback or a coach calls the plays. Quarterbacks typically inform the rest of the offense of the play in the huddle before the team lines up. The quarterback lines up behind the center to take the snap and then hands the ball off, throws it or runs with it.
  The primary role of the halfback, also known as the running back or tailback, is to carry the ball on running plays. Halfbacks may also serve as receivers. Fullbacks tend to be larger than halfbacks and function primarily as blockers, but they are sometimes used as runners in short-yardage situations and are seldom used in passing situations.
  The offensive line (OL) consists of several players whose primary function is to block members of the defensive line from tackling the ball carrier on running plays or sacking the quarterback on passing plays. The leader of the offensive line is the center, who is responsible for snapping the ball to the quarterback, blocking, and for making sure that the other linemen do their jobs during the play. On either side of the center are the guards (G), while tackles (T) line up outside the guards.
  The principal receivers are the wide receivers (WR) and the tight ends (TE). Wide receivers line up on or near the line of scrimmage, split outside the line. The main goal of the wide receiver is to catch passes thrown by the quarterback, but they may also function as decoys or as blockers during running plays. Tight ends line up outside the tackles and function both as receivers and as blockers.
caption: A quarterback for the Kiel Baltic Hurricanes under center, ready to take the snap
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