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, ringette, indoor broomball, bandy, rink bandy, rinkball, and sponge hockey 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. 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, and bandy. Based on the number of participants, ice hockey is the world's most popular winter team sport, followed by bandy.Winter sports have their own multi-sport events, such as the Winter Olympic Games and the Winter Universiade.