Iron (golf)

An iron is a type of club used in the sport of golf to propel the ball towards the hole. Irons typically have shorter shafts and smaller clubheads than woods, the head is made of solid iron or steel, and the head's primary feature is a large, flat, angled face, usually scored with grooves. Irons are used in a wide variety of situations, typically from the teeing ground on shorter holes, from the fairway or rough as the player approaches the green, and to extract the ball from hazards, such as bunkers or even shallow water hazards.

Irons are the most common type of club; a standard set of 14 golf clubs will usually contain between 7 and 11 irons, including wedges. Irons are customarily differentiated by a number from 1 to 10 (most commonly 3 to 9) that indicates the relative angle of loft on the clubface, although a set of irons will also vary in clubhead size, shaft length, and hence lie angle as the loft (and number) increase. Irons with higher loft than the numbered irons are called wedges, which are typically marked with a letter indicating their name, and are used for a variety of "utility" shots requiring short distance and/or a high launch angle.

Historically all irons were forged from a flat piece of metal, which produced a thin clubhead that resembled a blade. Modern investment casting processes enabled manufacturers to easily mass-produce clubs with consistent properties. This manufacturing process was first used by PING, and also made it possible to take weight out of the back of the clubhead and distribute it around the perimeter. These perimeter weighted, or cavity back, irons made it much easier to achieve consistent results even when striking the ball outside the "sweet spot", when compared with traditional bladed, or muscle back, irons.

In 1933, Willie Ogg – who at the time was serving as an advisory staff member for Wilson Staff – created a patented design for distributing weight away from the heel of the club head, moving it towards the “sweet spot” of the blade. This design feature was used in the Wilson "Ogg-mented" irons, the forerunner of perimeter-weighted or cavity back irons.

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