Mountain climbing is a hobby/job where people climb mountains. It may involve hiking, rock climbing, as well as crossing glaciers. Someone who does mountain climbing is called a mountain climber or mountaineer.
Mountain climbers use the strength of their arms and legs to climb up mountains. Many mountain climbers use ropes and wear special shoes and safety equipment . Most mountain climbers go up mountains as a hobby or as a recreational activity. A few do mountain climbing as an occupation or job. They get paid by outdoor clothing companies or universities to climb up mountains, or they are hired as a guide by recreational mountain climbers. Some are scientists who study mountains.