A golf ball is a ball

Ball

A ball is a round, usually spherical but sometimes ovoid, object with various uses. It is used in ball games, where the play of the game follows the state of the ball as it is hit, kicked or thrown by players. Balls can also be used for simpler activities, such as catch, marbles and juggling...

 designed to be used in the game of golf

Golf

Golf is a precision club and ball sport, in which competing players use many types of clubs to hit balls into a series of holes on a golf course using the fewest number of strokes....

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Under the Rules of Golf

Rules of golf

The rules of golf are a standard set of regulations and procedures by which the sport of golf should be played. They are jointly written and administered by the R&A the governing body of golf worldwide except in the United States and Mexico, which are the responsibility of the United States Golf...

, a golf ball weighs no more than 1.620 oz (45.93 grams), has a diameter not less than 1.680 in (42.67 mm), and performs within specified velocity, distance, and symmetry limits. Like golf clubs

Golf club (equipment)

A golf club is used to hit a golf ball in a game of golf. Each club is composed of a shaft with a grip and a clubhead. Woods are mainly used for long-distance fairway or tee shots; irons, the most versatile class, are used for a variety of shots; Hybrids that combine design elements of woods and...

, golf balls are subject to testing and approval by the Royal and Ancient Golf Club of St Andrews and the United States Golf Association

United States Golf Association

The United States Golf Association is the United States' national association of golf courses, clubs and facilities and the governing body of golf for the U.S. and Mexico. Together with The R&A, the USGA produces and interprets the Rules of Golf. The USGA also provides a national handicap system...

, and those that do not conform with regulations may not be used in competitions (Rule 5-1).
Wood

Wood

Wood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression...

en balls were the first used golf balls until the early 17th century, when the featherie ball added a new and exciting feature to the game of golf.