The 4-3 Defense is a popular formation used in American football, primarily by defensive teams. It consists of four defensive linemen and three linebackers, providing a balanced approach to stopping both the run and the pass. The four linemen create pressure on the quarterback, while the three linebackers are versatile players who can tackle, cover receivers, or rush the passer. This formation allows for flexibility in defensive strategies. The defensive coordinator can adjust player responsibilities based on the offensive formation they face. The 4-3 Defense is effective against various offensive schemes, making it a staple in many football programs.