Ski pole
Ski poles, also referred to as poles (in North America), sticks (UK), or stocks (Australia), are used by skiers for balance and propulsion. Modern ski poles are most commonly made from aluminum and carbon fiber, though materials such as bamboo are still used. Poles are used in alpine skiing, freestyle skiing (with the exception of aerials), and cross-country skiing. Ski jumpers do not use poles. History. , the earliest ski pole was found in Sweden and dates back to 3623 BC, while the earliest depiction of a man with a ski pole was found in Norway in the  form of a cave painting, dated at 4000 BC. Early skiers would use this pole for the purposes of balancing, braking, and turning. Alpine societies such as those in Nordic regions or the Altai mountains used their ski poles to hunt as well, giving them spear-like qualities. Skiers began to use two ski poles in 1741. This provided greater balance than one pole could provide and made pushing through the snow easier. Early ski poles were made of pine and bamboo, materials which today are used for novelty poles. US patents for steel ski poles began in 1933 when  John B. Dickson invented a new design calling for the use of steel as the shaft material. This construction was superseded by Edward L. Scott, who is credited with popularizing the lightweight aluminum ski pole in 1959, deriving his modern design from golf club shafts. This new stiff and lightweight pole made it easier for skiers to pole-plant and initiate fast, short turns. The most modern material used in ski pole production is carbon fiber. A patent has been filed on a biocomposite material that can be used for ski poles, but this design has yet to be manufactured . Axel Composites has a patent for carbon fiber ski poles dating back to 1975, however, inventor David P. Goode's improved design from 1989 became the first widely produced. The carbon fiber pole builds on the same qualities of the aluminum pole: lightness and stiffness while being extremely strong. Pole types. Alpine skiing. Poles are used in alpine skiing to add propulsion and to aid in controlling upper body position at turn initiation. Racing poles have their own unique distinctions. Super giant slalom, downhill, and speed skiing poles are designed to bend around the skier's body while in a  tuck position to minimize drag. In slalom skiing, straight poles are used due to the reduced speeds and increased reliance on poles. Slalom poles will often come with a guard attached to the grip for the purpose of deflecting gates. Giant slalom skiers choose a straight or bent pole based on personal preference and situation; giant slalom courses can vary greatly in speed and in the case of slower courses, aerodynamic drag does not have as great a factor. Cross-country skiing. Poles enable cross-country skiers to apply power to the snow, using arm motion; poles can also provide  stability. In competitive cross-country skiing, poling technique is essential, especially so during a mass start in which double-poling is the main means of propulsion. Longer poles are used for cross country because of different techniques. Pole length for classic (aka diagonal-stride) technique is typically measured from the ground to the skier's armpit. For skating (aka freestyle) technique the length of the pole is typically from the ground to the skier's upper lip. These length selections balance between maximum thrust and technique considerations. Most Nordic ski pole manufacturers have sizing charts available. Nordic walking. Nordic walking  poles are largely similar to composite cross-country ski poles, just shorter in length and with a basket smaller than that of the racing cross country ski pole. The Nordic walking pole strap resembles a fingerless glove and is similar to the racing cross country ski pole strap.