Mountaineering or mountain climbing is the sport, hobby or profession of hiking, skiing, and climbing mountains. While mountaineering began as attempts to reach the highest point of unclimbed mountains it has branched into specializations that address different aspects of the mountain and consists of three areas: rock-craft, snow-craft and skiing, depending on whether the route chosen is over rock, snow or ice. All require experience, athletic ability, and technical knowledge to maintain safety.
The UIAA or Union Internationale des Associations d’Alpinisme is the world governing body in mountaineering and climbing, addressing issues like access, medical, mountain protection, safety, youth and ice climbing.
Reference: Wikipedia Mountaineering