Out of bounds

In sports, out of bounds (or out-of-bounds) refers to being outside the playing boundaries of the field. Due to the chaotic nature of play, it is normal in many sports for players and/or the ball to go out of bounds frequently during a game. The legality of going out of bounds (intentionally or not), and the ease of prevention, vary by sport. In some cases, players may intentionally go or send the ball out of bounds when it is to their advantage.

Skiing
In skiing, an out of bounds area is considered one that is outside of the area owned/serviced by a ski resort. Out of bounds areas can either be accessed by ducking under a rope or fence, or through marked gates. Usually, if one is caught 'cutting a rope', one will lose skiing privileges at the ski resort; depending on where one does so, they may also be arrested for trespassing. Out of bounds areas are not serviced by any type of lift, thus one must usually hike out of the area. Also, out of bounds areas are not serviced by a resorts ski patrol and are not checked for avalanche potential, thus one must be properly equipped for avalanche rescue and understand that a rescue may be incredibly costly.

Gridiron football
In gridiron football, a play is considered to be dead if a ball or the player carrying the ball goes out of bounds.

A ball thrown out of bounds is considered an incomplete pass, even if it is caught.

In the NFL, the clock stops whenever a player carrying the ball steps out of bounds or fumbles the ball out of bounds. Within the last 2 minutes of the first half, the last 5 minutes of the game, or after a change of possession, the clock remains stopped until the next snap; at all other times, the clock restarts when the referee signals indicating that the ball has been placed for the next down.

In arena football, the field is walled so that play can almost never go out of bounds. At all other times, the clock keeps ticking. In college football, the clock stops when the ballcarrier goes out of bounds. If there are more than two minutes left in either half, the clock resumes when the umpire marks the ball as ready for the next play. If there are less than two minutes left in the half, the clock resumes upon the next play.

If the player with the ball goes out of bounds in his own end zone, in most cases, it is considered to be a safety in favor of the other team.

A kickoff that goes out of bounds is a penalty. Up through 1986, this required the kicking team to rekick the ball from five yards behind the spot of the original kickoff, unless the penalty was declined by the receiving team. In 1987, the NFL instituted a new rule, where the ball would be awarded to the receiving team five yards ahead of the spot where it went out of bounds.

In Canadian football, if a fumble goes out of bounds, the team of the last player to touch it gets possession.

Baseball
In major league baseball, it is possible in baseball for a dugout to be a factor in play. MLB rule 6.05(a) states that a fielder may reach into a dugout to catch a fly ball as long as one or both feet is on or over the playing field, and does not have a foot on the ground in the dugout when making the catch. MLB universal ground rules state that the player may subsequently enter the dugout after making the catch if his momentum is carrying him that way, but if he falls in the dugout as a result, the catch is allowed but baserunners advance in accordance with Rule 7.04(c).[3]

A live ball entering a dugout becomes dead and the batter-runner and any baserunners advance in accordance with Rule 7.04(c). However, a live ball bouncing off a dugout railing, if present, is still in play (unless a foul ball). Due to the dugouts' location in foul territory, live balls entering dugouts usually only occur after an errant throw by the defensive team.

Individual leagues at levels below MLB are free to set their own rules governing the dugouts as is appropriate for their league's ballparks and playing level. For example, the rule governing reaching into dugouts to catch fly balls would not apply in leagues where the dugouts are separated from the field by a chain-link fence that is taller than the players.

Basketball
When the ball goes out of bounds, it shall be thrown into the field and played by the first person touching it. In case of dispute, the umpire shall throw it straight into the field. The thrower-in is allowed five seconds. If he holds it longer, it shall go to the opponent. If any side persists in delaying the game, the umpire shall call a foul on that side.

Australian rules football
In Australian rules football, the ball is considered out of bounds when the whole of the ball is outside the boundary line or any part of the ball touches the behind post.

Sending the ball out of bounds will result in a free kick against the team sending the ball out of bounds when the ball goes out of bounds from a kick on the full (without bouncing or being touched by another player), or if forced deliberately out of bounds by a player. If the ball goes out of bound from a kick-in after a behind is scored without being touched by any player, or forced out of bounds on the full from a hit-out in a ruck contest after a throw-in, the ball is deemed to be deliberately out of bounds. In any other case, the boundary umpire will throw the ball in from the boundary line.

Golf
In Golf, "Out of Bounds" is beyond the boundaries of the golf course or any part of the course so marked by the committee in charge of the competition or the golf course.

If a ball is out of bounds, the player must play a ball, under penalty of one stroke, as nearly as possible at the spot from which the original ball was last played.

Reference: Rules of Golf 2012-2015, Rule 27-1 b. Ball Out of Bounds, published by the R&A - and approved by the United States Golf Association (USGA).

A golf ball is out of bounds when all of it lies out of bounds. A player may stand out of bounds to play a ball lying within bounds.

Reference: Rules of Golf 2012-2015, Section II Definitions.