A golf club is a piece of sporting equipment 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 irons are becoming increasingly popular; putters are used mainly on the green to roll the ball into the cup. A standard set consists of 14 golf clubs, and while there are traditional combinations sold at retail as matched sets, players are free to bring any combination of 14 or fewer legal clubs.
An important variation in different clubs is loft, or the angle between the club's face and the vertical plane. It is loft that is the primary determinant of the ascending trajectory of the golf ball, with the tangential angle of the clubhead's swing arc at impact being a secondary and relatively minor consideration (though these small changes in swing angle can nevertheless have a significant influence on launch angle when using low-lofted clubs). The impact of the club compresses the ball, while grooves on the clubface give the ball backspin. Together, the compression and backspin create lift. The majority of woods and irons are labeled with a number; higher numbers indicate shorter shafts and higher lofts, which give the ball a higher and shorter trajectory.
A golf ball is a special ball designed to be used in the game of golf.
Under the rules of 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 balls are subject to testing and approval by the R&A (formerly part of the Royal and Ancient Golf Club of St Andrews) and the United States Golf Association, and those that do not conform with regulations may not be used in competitions (Rule 5–1).