just specific routes to run on specific plays), but also allows for more efficient communication (one word does the job of complex sentences of coded words and numbers) and allows for a greater flexibility by allowing every play to be run from every possible formation. Defensive strategy The goal of defensive strategy is to prevent the opposing offense from gaining yards and scoring points, either by preventing the offense from advancing the ball beyond the line of scrimmage or by the defense taking the ball away from the offense (referred to as a turnover) and scoring points themselves. Defensive players On defense, there are three types of players: linemen, linebackers, and defensive backs (also called secondary players). These players' specific positions on the field and duties during the game vary depending on the type of defense being used as well as the kind of offense the defense is facing. Defensive line The defensive line lines up in front of the offensive line. The defensive lineman's responsibility is to prevent the offensive line from opening up running lanes for the running back or to sack the quarterback, depending on whether the play is a passing or running play. Most of the time, defensive linemen attack the offensive line but in some plays they drop back in pass coverage to confuse the opposite team. Defensive nose guard: The nose guard ("NG"), also known as a nose tackle ("NT"), lines up across from the center. Nose guards are among the biggest players on the field and mainly are used to push back the center or the guard to stop a running play or to move the offensive linemen to where the linebackers can rush the quarterback. Defensive tackle: The defensive tackle ("DT") lines up against the guard or center on the offensive line. Defensive tackles are generally the biggest and most powerful players on defense; many of them are of the same size as the offensive line. They tend to be more the "run-stopping" type rather than being good at rushing the quarterback themselves. Defensive end: Defensive ends ("DE") line up just outside the offensive tackle. Defensive ends need to be strong to be able to not be pushed back by the offensive line, yet fast enough to run around the offensive tackle. There are different types of defensive ends; some are about as strong as DTs and are considered more adept at