Linebacker (LB) is a playing position in gridiron football. Linebackers are members of the defensive team, and line up three to five yards behind the line of scrimmage and the defensive linemen. They are the "middle ground" of defenders, playing closer to the line of scrimmage than the defensive backs (secondary), but farther back than the defensive linemen.
In white jerseys, Lance Briggs (#55) and Brian Urlacher (#54) of the Chicago Bears, are positioned as linebackers on Lambeau Field in 2011.
The University of Michigan is credited with creating the linebacker position, which was first played by Germany Schulz
Chuck Bednarik of the Philadelphia Eagles, a first round draft selection in the 1949 NFL Draft and member of the Pro Football Hall of Fame, is considered one of the hardest hitting and best linebackers in NFL history; his November 20, 1960 tackle of Frank Gifford, a New York Giants running back, is known simply as "The Hit" and is considered one of the hardest hits in the league's history.
American football positions
In American football, the specific role that a player takes on the field is referred to as their "position". Under the modern rules of American football, both teams are allowed 11 players on the field at one time and have "unlimited free substitutions", meaning that they may change any number of players during any "dead ball" situation. This has resulted in the development of three task-specific "platoons" of players within any single team: the offense, the defense, and "special teams". Within these three separate "platoons", various positions exist depending on the jobs that the players are doing.
The offensive line (on left, in orange jerseys) consists of a center (with ball in hand ready to snap) with two guards on either side, and two tackles.
A wide receiver (No. 87, in white) begins a play in the flanker position
The four defensive linemen (in red) have their hands on the ground in a "three point stance"
This defense (in white) is in a base 4–3 set. Just behind the four defensive linemen (whose hands are on the ground) are three linebackers (Nos. 55, 3 and 16), and further back are two safeties (numbers 24 and 44). The two cornerbacks are off screen to the left and right.