4-4 Football Defense
The 4-4 defense is a basic defensive formation in the game of football. 4-4 Defensive scheme has two defensive ends (DE), one on each end of the line, and two defensive tackles (DT) in between. Spread out behind the defensive line are the four linebackers (LB). The 4-4 defense is designed to stop the wide running game as well as the short passing game. Two cornerbacks (CB), one on each side of the field, line up to cover the wide receivers. There is just one safety. The exact position of the defensive backs (cornerbacks and safety) depends on the type of pass coverage they are in.
4-4 defense uses only single safety. It also exposes weakness in deep pass coverage since cornerbacks are in man-to-man coverage. Safety must commit early in a play to help out one of the cornerback.
The 4-4 uses four down linemen, four linebackers, two cornerbacks, and a safety. Stunts are a common component of this defensive set, usually with the some or all of the linemen stunting left or right and the inside linebackers stunting in the opposite direction. A wide range of possible stunts and blitzes are possible. However, it requires above avergae skills on part of cornerbacks. The 4-4, also known as the "Stack" defense, relies on quickness, particularly quickness in pursuit. In order to run the 4-4 on a regular basis, the interior down linemen must be players of considerable substance. In case of blitzes, pass rush must get to quarterback quickly in order to minimize deep pass threat.

