In (American) football, when the offensive team ends a down with the ball behind their own end zone line, the play is ruled a safety, and the defensive team is awarded two points. The offensive team then must either punt or kick the ball from their own 20-yard line to the defensive team.

The safety most often occurs when the quarterback or running back is tackled in his own end zone. However, a safety can also occur when a ball is batted through the back or side of the end zone. Players will occasionally do this on purpose during a loose ball scramble to keep the defensive team from scoring a touchdown. An intentional safety can also occur near the end of game when the winning team doesn't want to risk having a punt blocked, and feels that a free kick is more valuable than two points.

A safety is also awarded when a quarterback is called for intentional grounding in the end zone, or when any player is called for offensive holding in the end zone.


 
If that wasn't confusing enough, the safety is also the name of a defensive position on the field. The safety is part of the defensive backfield, furthest away from the line of scrimmage. The primary job of the safety is to assist the cornerbacks in pass coverage. In other schemes, safeties are asked to cover man-to-man, blitz the quarterback, or act as an additional run stopper.

In most defensive schemes, there are two safeties - the strong safety and free safety. The strong safety lines up on the "strong" side of the field (the side where the tight end lines up), and is usually a more physical player and a better tackler than the free safety. The free safety lines up on the opposite side of the field, and is generally allowed to roam more freely. The free safety is usually a better pass defender than the stong safety.