Hash marks in football are two sets of dashes that run through the middle of the field. The hash marks are used to align players at the start of a down. The ball is either placed on the closest hash mark or left in between the sets. If the ball is ruled dead in between the hash marks it is left there. If the ball is ruled dead outside the hash marks near the sidelines, the closest hash mark is used. The distance between hash marks differ from high school football, college football, and the NFL.