Hazards
Holes often include hazards, which are special areas that have additional rules for play, and are generally of two types: (1) water hazards, such as ponds, lakes, and rivers; and (2) bunkers, or sand traps.
Special rules apply to playing a ball that falls in a hazard. For example, a player may not touch the ground or water with his club before playing the ball, not even for a practice swing. A ball in any hazard may be played as it lies without penalty. If it cannot be played from the hazard, the ball may be hit from another location, generally with a penalty of one stroke. The Rules of Golf specify exactly the point from which the ball may be played outside a hazard. Bunkers are small to medium areas, usually lower than the firway but of varying topology, that are filled with sand and generally incorporate a raised lip or barrier. It is more difficult to play the ball from sand than from grass, as the ball may embed itself into the sand, and the loose nature of the sand and more severe sloping of many bunkers make taking one's stance more difficult. As in any hazard, a ball in a bunker must be played without touching the sand with the club except during the stroke, and loose impediments (leaves, stones, twigs) must not be moved before making the stroke.
Courses may also have other design features which the skilled player will avoid; there are earth bunkers (pits or depressions in the ground that are not filled with sand but require a lofted shot to escape), high grass and other dense vegetation, trees or shrubs, ravines and other rocky areas, steep inclines, etc.; while disadvantageous to play from, these are typically not considered "hazards" unless specifically designated so by the course (a ravine or creekbed may be termed a "water hazard" even if completely dry).
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