Ski

Skis are runners, attached to the user's feet, designed to glide over snow. Typically employed in pairs, skis are attached to ski boots with ski bindings, with either a free, lockable, or partially secured heel. For climbing slopes, ski skins can be affixed to the base of each ski to prevent them from sliding backwards. Originally used as a means of travel over snow, skis have become specialized for recreational and competitive alpine and cross-country skiing.

The word ski comes from the Old Norse word skíð which means "cleft wood," "stick of wood," or "ski". In Old Norse common phrases describing skiing were fara á skíðum (to travel, move fast on skis), renna (to move swiftly) and skríða á skíðum (to stride on skis). In Norwegian this word is usually pronounced [ˈʂiː]. In Swedish, another language evolved from Old Norse, the word is skidor (plural, pronounced [ˈɧîːdʊr]; singular: skida). The modern Norwegian word ski and the Swedish word skid have largely retained the Old Norse meaning in words for split firewood, wood building materials (such as bargeboards) and roundpole fence.

English and French use the original Norwegian spelling ski, and modify the pronunciation. Before 1920, English often called them skee and snow-shoe. In Italian, it is pronounced similarly to Norwegian, but the spelling is modified accordingly: sci [ˈʃi]. Portuguese and Spanish adapt the word to their linguistic rules: esqui and esquí. In German, spellings Ski and Schi are in use, both pronounced [ˈʃiː]. In Dutch, the word is ski and the pronunciation was originally [ˈɕiː] as in Norwegian, but since approximately the 1960s changed to [ˈskiː]. In Welsh the word is spelled sgi. Many languages make a verb form out of the noun, such as to ski in English, skier in French, esquiar in Spanish and Portuguese, sciare in Italian, skiën in Dutch, or Schi laufen or Schi fahren (as above also Ski laufen or Ski fahren) in German. Norwegian and Swedish do not form a verb from the noun.

Finnish has its own ancient words for skis and skiing: "ski" is suksi and "skiing" is hiihtää. The word suksi goes back to the Proto-Uralic period, with cognates such as Erzya soks, Mansi tåut and Nganasan tuta. The Sami also have their own words for "skis" and "skiing": for example, the Lule Sami word for "ski" is sabek and skis are called sabega. The Sami use cuoigat for the verb "to ski".

Skis appeared before the wheel, with the oldest wooden skis found in Russia (c. 6300–5000 BCE), Sweden (c. 5200 BCE) and Norway (c. 3200 BCE) respectively.

These early skis were not designed for recreation or speed; their sole purpose was to keep the user on top of the snow, as when hunting or at war. Early skis were generally accompanied by a walking stick to help the user maintain balance.

Nordic ski technology was adapted during the early 20th century to enable skiers to turn at higher speeds. New ski and ski binding designs, coupled with the introduction of ski lifts to carry skiers up slopes, enabled the development of alpine skis. Meanwhile, advances in technology in the Nordic camp allowed for the development of special skis for skating and ski jumping.

This type of ski was used at least in northern Finland and Sweden until the 1930s. On one leg, the skier wore a long straight non-arching ski for sliding, and on the other a shorter ski for kicking. The bottom of the short ski was either plain or covered with animal skin to aid this use, while the long ski supporting the weight of the skier was treated with animal fat in similar manner to modern ski waxing. Early record of this type of skis survives in works of Olaus Magnus. He associates them to Sami people and gives Sami names of savek and golos for the plain and skinned short ski. Finnish names for these are lyly and kalhu for the long and short ski.