American football strategy American football strategy concerns the deployment of offensive , defensive , and special teams players in American football . Offensive Strategy . The goal of the offense is to score points . In order to accomplish this goal , coaches and players plan and execute plays - based on a variety of factors : The players involved , the opponent ’ s defensive strategy , the amount of time remaining before halftime or the end of the game , and the number of points needed to score to win the game . Strategically , the offense can prolong their possession of the ball to prevent the opponent from scoring . Offensive Players . On offense , there are three types of players : linemen , backs , and receivers . These particular players ' position and duties on the field vary from one offensive scheme to another . The position names ( as well as the abbreviations recognized by coaches , players , and fans ) vary from one team ' s playbook to another , but these are the ones most commonly used : Backs . Backs are so named because they line up behind ( in back of ) the line of scrimmage at the start of the play . Offensive formations . Before the ball is snapped the offensive team lines up in a formation . The type of formation used is determined by the game situation . Teams often have " special formations " that they only use in obvious passing situations , short yardage , goal line situations , or formations they have developed for that particular game just to confuse the defense . There are a nearly unlimited number of possible formations - a few of the more common ones are listed below : Offensive plays . When the team is in formation and the quarterback gives a signal , either by calling out instructions or giving a non - verbal cue ( a so - called " silent count " ) , the center snaps the ball to the quarterback and a play begins . Running plays . A running play occurs when the quarterback hands the ball to another player , who then attempts to carry the ball past the line of scrimmage and gain yards , or the quarterback keeps the ball himself and runs beyond the line of scrimmage . In both cases , the offensive line ' s main job is to run block , preventing the defensive players from tackling the ball carrier . The choice of running play depends on the strengths of an offensive team , the weaknesses of the defense they are opposing , and the distance needed to score a touchdown or gain a first down . There are many kinds of running plays , including : Passing plays . When a passing play occurs , the backs and receivers run specific patterns , or routes , and the quarterback throws the ball to one of the players . On these plays , the offensive line ' s main job is to prevent defensive players from tackling the quarterback before he throws the ball ( a " sack " ) or disrupting the quarterback in any other way during the play . When successful , passing plays tend to cover more ground than running plays , so they are often used when the offensive teams needs to gain a large amount of yards . Different kinds of pass plays include : Eligible Receivers . One general rule teams must take into account when creating their passing strategy is that only certain players are allowed to catch forward passes . If a player who is not an eligible receiver receives a thrown pass , the team could be penalized . However , if prior to a play the team reports to the referee that a normally ineligible receiver will act as an eligible receiver for one play , that player is allowed to catch passes . Teams will use this strategy from time to time to confuse the defense or force them to devote more attention to possible pass - catchers . Specific offensive strategies . Using a combination of passing plays and running plays , the offense tries to gain the yards needed for a first down , touchdown , or field goal . Over the years several football coaches and offensive coordinators have developed some well - known and widely - used offensive strategies : Play calling systems . Distinct from the offensive strategies or philosophies , which govern how a team moves the ball down the field , whether a team relies on downfield passes , short passes , inside runs , etc . are the ways in which plays are called . These play calling system s often developed alongside certain offensive strategies , though the systems themselves can work with any strategy . The differences between the systems focus on the specific language used to communicate plays to players . In the NFL , three basic systems predominate : 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 linemen line 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 . Linebackers . Linebacker s stand behind the defensive linemen or set themselves up on the line of scrimmage . Depending on the type of defensive strategy being used , a linebacker ' s responsibilities can include helping to stop the run , rushing the quarterback , or dropping back in pass protection . Defensive backs . Defensive backs stand behind the linebackers . Their primary responsibility is pass coverage , although they can also be involved in stopping the run or rushing the quarterback . Defensive formations . The most common way to describe a basic defensive formation is by stating the number of linemen involved followed by the number of linebackers . The number of defensive backs is usually not mentioned , though if it is , ( such as in the " 3 - 3 - 5 " ) , the number typically appears after the number of linebackers , thus the formula would go ( # of linemen ) - ( # of linebackers ) - ( # of defensive backs [ if stated ] ) in these situations . This naming rule does not always apply when the personnel for a certain formation are lined up in a way that changes the function of the players in the defense . A good example to help explain this would be the " 3 - 5 - 3 , " which actually uses the 3 - 3 - 5 personnel , but has the five defensive backs arranged with " 3 deep " , thus grouping the other two defensive backs with the linebacker group . By far the most common alignments are four down linemen and three linebackers ( a " 4 - 3 " defense ) , or three down linemen and four linebackers ( " 3 - 4 " ) , but other formations such as five linemen and two linebackers ( " 5 - 2 " ) , or three linemen , three linebackers , and five defensive backs ( " 3 - 3 - 5 " ) are also used by a number of teams . On plays where the defense expects the offense to pass , naming emphasis is often placed on the number of defensive backs . In a basic 4 - 3 or 3 - 4 defense , there are four defensive backs on the field ( 2 cornerbacks [ CB ] , 1 strong safety [ SS ] , and 1 free safety [ FS ] ) . When one of the linemen or linebackers is removed and an additional defensive back is added , common alignments of these five defensive back packages are the " nickel " package , which includes 3 CB , 1 SS , and 1 FS , and the " 3 - 3 - 5 , " which is a nickel package variant that includes either 2 CB , 2 SS , and 1 FS , or 3 CB , 1 SS , and 1 FS like the standard nickel package . When a sixth defensive back is inserted , it is known as a " dime " package ( 4CB , 1SS , 1FS ) . In rare instances when a seventh defensive back is inserted , it is known as a " quarter " package ( 5CB , 1SS , 1FS " or " 4CB , 2SS , 1FS ) . As with offensive formations , there are many combinations that can be used to set up a defense . Unusual defensive alignments are constantly used in an effort to neutralize a given offense ' s strengths . In winning Super Bowl XXV , the New York Giants played with two down linemen , four linebackers and five defensive backs , a strategy that prevented their opponents , the Buffalo Bills , a team with a strong passing game , from completing long passes . In a 2004 game , the New England Patriots used no down linemen and seven linebackers for two plays against the Miami Dolphins . Some of the more familiar defensive formations include : Defensive plays . The defense must wait until the ball is snapped by the opposing center before they can move across the line of scrimmage or otherwise engage any of the offensive players . Once an opposing offense has broken their huddle and lined up in their formation , defensive players often call out instructions to each other to make last - second adjustments to the defense . Run defense . To prevent the opposing offense from gaining yards on the ground , a defense might put more emphasis on their run defense . This generally involves placing more players close to the line of scrimmage to get to the ball carrier more quickly . This strategy is often used when the opposing offense only needs to gain a few yards to make a first down or score a touchdown . Pass defense . When the defense believes the opposing offense will pass the ball , they go into pass defense . There are two general schemes for defending against the pass : Blitz . There are times when a defense believes that the best way to stop the offense is to rush the quarterback , which involves sending several players charging at the line of scrimmage in an attempt to tackle the quarterback before he can throw the ball or hand it to another player . Any player on the defense is allowed to rush the quarterback , and many schemes have been developed over 50 years that involve complicated or unusual blitz “ packages . ” Specific defensive strategies . Defensive strategies differ somewhat from offensive strategies in that , unlike offenses that have very specific , detailed plans and assignments for each player , defenses are more reactive , with each player ’ s general goal being to “ stop the offense ” by tackling the ball carrier , breaking up passing plays , taking the ball away from the offense , or sacking the quarterback . Whereas precision and timing are among the most important parts of offensive strategy , defensive strategies often emphasize aggressiveness and the ability to react to plays as they develop . Nevertheless , there are many defensive strategies that have been developed over the years that coaches use as a framework for their general defense , making specific adjustments depending on the capabilities of their players and the opponent they are facing . Some of the most commonly known and used defensive strategies include : Special teams strategy . A special team is the group of players who take the field during kickoffs , free kicks , punts , and field goal attempts . Most football teams ' special teams include one or more kickers , a long snapper ( who specializes in accurate snaps over long distances ) , kick returners who catch and carry the ball after it is kicked by the opposing team , and blockers who defend during kicks and returns . Most special teams are made up of players who act as backups or substitutes on the team ' s offensive and defensive units . Because of the risk of injury , it is uncommon for a starting offensive or defensive player to also play on a special teams unit . A variety of strategic plays can be attempted during kickoffs , punts , and field goals — to surprise the opposition and score points , gain yardage or first downs , or recover possession of the kicked ball . Kickoffs . A kickoff occurs at the beginning of each half , overtime period ( not in college ) , and following each touchdown , successful field goal , or safety . Strategically , the coach of the other team may choose to have his players kick the ball in one of several ways : Punts . The " no punting " strategy is one that forsakes the practice of punting and instead attempts to make fourth down conversions on as many plays as possible . It has been implemented at Pulaski Academy , a top - ranked prep school , and has been advocated by Gregg Easterbrook in his " Tuesday Morning Quarterback " column and by author L . Jon Wertheim . Field goals . Field goals are worth one point after a scored touchdown , or three points in the event that a team does not score a touchdown but feels it is positioned close enough for the kicker to make the attempt . Kick and punt returns . Downing the ball . If , for whatever reason , the receiving team does not catch the ball , the kicking team may move into position and try to down it as close as possible to the opposing team ' s end zone . This is achieved by surrounding the ball and allowing it to roll or bounce , without touching it , as close as possible to the end zone . If the ball appears to be rolling or bouncing into the end zone , a player may run in front of the goal line and attempt to bat it down or catch it . If a member of the kicking team touches or catches the ball before a member of the receiving team does so , the ball is blown dead by the official when he has judged that the returner is not going to pick up the ball and return it , or the kicking team picks the ball up and hands it to the official . Once the whistle is blown the play is over and the receiving team takes possession at the spot the ball was spotted by the official . Thus it is strategically important for kicking teams to get as close to the ball as possible after a punt , so that they may quickly tackle a returner , down the ball as close to the opposing team ' s end zone as possible , and ( if possible ) recover the ball after a fumble and regain possession of the ball .