Winter sports or winter activities are competitive sports or non-competitive recreational activities which are played on snow or ice. Most are variations of skiing, ice skating and sledding. Traditionally, such games were only played in cold areas during winter, but artificial snow and artificial ice allow more flexibility. Playing areas and fields consist of either snow or ice.
Artificial ice can be used to provide ice rinks for ice skating, ice hockey, para ice hockey, ringette, broomball, bandy, rink bandy, rinkball, and spongee in a milder climate. The sport of speed skating uses a frozen circular track of ice, but in some facilities the track is combined in an enclosed area used for sports requiring an ice rink or the rink itself is used. Alternatively, ice cross downhill uses a track with various levels of elevation and a combination of bends. Long distance skating (a.k.a. "marathon skating") such as tour skating is only performed outdoors and uses the available natural ice from frozen lakes, ponds, and marshes. Tour skating at times includes speed skaters, though tour skates are more common.
Common individual sports include cross-country skiing, alpine skiing, snowboarding, ski jumping, speed skating, figure skating, luge, skeleton, bobsleigh, ski orienteering and snowmobiling.
Common team sports include ice hockey, ringette, broomball (on either an indoor ice rink, or an outdoor ice rink or field of snow), curling, rinkball, and bandy. Based on the number of participants, ice hockey is the world's most popular winter team sport, followed by bandy.
Winter sports at times have their own multi-sport events, such as the Winter Olympic Games and the Winter Universiade.
In the early days of the Olympics there was not much differentiation between the summer and winter games. These confusions would span from around the late 1890s until the early to mid 1900s. During this time, some sports considered to be winter sports and played or performed during the Olympic Winter Games today, would be held during the Olympic Summer Games. It was originally wanted to keep all of the Olympic sports together under one event and program, but due to environmental demands of some sports, it had to be separated. 
Snow and ice during the winter time has enabled sliding as a means of transportation, using sledges, skis and skates. This also led to different pastimes and sports being developed in the winter season as compared to other times of the year. Naturally, winter sports are more popular in countries with longer winter seasons.
In the European Alps, St. Moritz became a popular winter resort in 1864.
While most winter sports are played outside, ice hockey, speed skating and to some extent bandy have moved indoors starting in the mid-20th century. Indoor ice rinks with artificial ice allow ice skating and hockey to be played in hot climates.
Outdoor winter sports will likely be severely impacted because of climate change in the next century.
Note: the Olympic rings next to a sport indicates that this particular sport is included in the Winter Olympic Games, as of the 2014 Winter Olympics in Sochi. The Paralympic logo indicates the same for a sport not in the Olympics but in the Winter Paralympic Games.
Sports that use sleds going down ice tracks or pulled by something:
Some sports are competed in (or simply enjoyed) on a more casual basis, often by children:
You can make a strong case that the origins of modern winter sports lie here, starting in the 1860's with hotelier Johannes Badrutt, who welcomed a steady stream of well-heeled British guests to his small Kulm Hotel.
The launching of the Cook excursions in Britain (1841), the appearance of the first Baedekker guide (1843), the inauguration of a winter "season" in Saint Moritz (1864), the creation of Yellowstone (1877): these were the important markers of its growth path [mass tourism].