A sand-filled depression near the green or fairway is known as a bunker or sand trap. Because hitting the ball out of the bunker is tough, entering it is considered a punishment for a golfer who misses the target with the previous stroke. A "sand wedge" is a club used to retrieve the ball from a bunker, a process that requires a high level of ability. After a player has finished using the bunker, the golfer or the player's caddie must rake the sand that has been disturbed during play. Playing from a bunker is governed by specific golf rules. A player may not, for example, ground his or her club in a bunker; that is, the club must not touch the ground before the swing.
In golf course design, there are three types of bunkers, all of which are intended to obstruct the golfer's path toward the green. Fairway bunkers are positioned to the sides of the fairway or even in the middle of the fairway and are designed to catch wayward tee shots on par 4 and par 5 holes. Greenside bunkers, which are positioned close and around the green, are designed to catch wayward approach shots on long holes and tee shots on par 3 holes. Waste bunkers are huge natural sandy regions that are typically found on links courses; they are not considered hazards by the rules of golf, hence golfers are allowed to lightly grind a club in the area around the ball, unlike fairway or greenside bunkers, and remove stray obstacles.
