Alpine Skiing - The term "skiing" commonly refers to alpine skiing where one visits a ski resort, purchases a lift ticket, dons cold-weather clothing, skis, ski boots and often ski poles, and embarks on a chairlift, gondola lift, or other means of mechanical uphill transport. Upon reaching the summit, the skier disembarks from the ski lift and travels downhill, propelled by gravity, usually along a marked route known as a piste, "run," "trail," or "slope". Most ski resorts use mechanical equipment to "groom," or pack down and smooth, the snow surface on certain ski trails. Alpine skiing developed in the Alps beginning in 1889. In Winterthur, Switzerland, Odd Kjelsberg may have been the first person in the Alps to try skiing. Previous to this time, the predominate Alpine winter sport had been tobogganing.
Alpine Freestyle - This kind of skiing could be called acrobatics on skis. Alpine freestyle was pioneered by Stein Eriksen in 1962. It developed in the 1970s into a style called Hotdogging. More recently Alpine freestyle has evolved into the current style called Jib skiing or freestyle skiing, a new style of skiing that started in the late 1990s. In this type of skiing, skiers use jumps also called kickers,or rails to do urban style aerial tricks.
Back Country Skiing - Also called Nordic touring. In the Alps where skiers can easily ski from area to area, off piste and backcountry skiing are indistinguishable. In North America however, where chairlifts either aren't allowed or are impractical for touring, skiers typically use Nordic style equipment which is more suitable for skiing up-hill. The heels of the bindings always remain free, unlike off piste bindings which can be locked down.
Cross-Country Racing - Cross-country skiing takes its name from a type of ski race that is one third up, one third down, and one third flat. The name distinguishes it from other types of ski races and competition such as downhill racing, slalom racing, and Nordic jumping. Cross-country races can be either freestyle or classic. In freestyle racing, any technique is allowed as long as it is human powered and on skis. In a classic race, skating techniques are prohibited.
Kite skiing and para-skiing is skiing done while being pulled or carried by a parasail, hangglider, or kite.Skiing on artificial ski slopes Dry slope skiing is a year-round sport in countries like the UK where the snow cover is insufficient for traditional skiing. There is a thriving race programme on British slopes.

Nordic Skiing: Also called Cross-country skiing. Worldwide, Nordic skiing may be the most popular form of skiing since it does not require a specially ski area. Typically after donning appropriate clothing, the skier goes outside and skis in a local park or even on a snowy street. Nordic skiing is the oldest form of skiing and was developed in Scandinavia as a way of traveling in the winter.        

Off-Piste Skiing (also called Randonnée, ski mountaineering, and Alpine touring). Off piste skiing includes skiing in unmarked or unpatrolled areas either within the ski resort's boundaries or in the backcountry, frequently amongst trees ("glade skiing"), usually in pursuit of fresh fallen snow, known as powder. Off piste skiers typically use Alpine style skis and boots but with bindings that can be released at the heel for easier movement on flat and uphill terrain. For traveling up-hill off piste skiers often use skins, strips of fabric temporarily glued to the bottoms of the skis. Skiing or snowboarding outside a ski resort's boundaries, is also known as off-piste skiing. In most countries where skiing is popular - France, Norway, Sweden, Switzerland and Canada- this is permitted. While in the United States, off-piste skiing is not permitted at some resorts, in Iran, off-piste skiing is not permitted at any resorts. Regulations vary by ski area; many ski resorts prohibit it outright and some simply post warning signs that skiers are leaving the patrolled ski area boundaries. In all regions, off piste skiing is perfectly legal, provided the skier has not skied from a designated ski area after buying a ticket. Some areas do allow departure from the ski area while on skis, others do not. Normally, skiing out of bounds results in loss of the lift ticket and banishment from the ski area. On the other hand, skiing in a closed area is illegal and likely to land a skier in jail. In Europe and Canada off piste skiing and skiing out of bounds and departing from/returning to ski areas is generally allowed. However, lost or overdue backcountry travellers are usually held responsible for the cost of search-and-rescue service if uninsured. Backcountry skiers traveling in steep terrain prone to avalanches are encouraged to take avalanche training, travel with other experienced people, and carry special equipment for self-rescue. It is recommended that skiers make the local ski patrol aware of where they are going if they stray off piste in case of avalanches or bad weather that could put skiers in danger.

Telemark Skiing - Telemark skiers use flexible ski boots, either leather or plastic, and do not have their heels locked to the skis. Alpine skiers use stiffer plastic, non-flexible boots and have their heels locked to the skis with releaseable bindings.