Yaks are herbivores that eat herbs, shrubs, grasses, lichen and moss. Domesticated yaks are used for pulling ploughs, transporting goods across mountains and providing milk and dairy products such as butter and cheese. Yaks will not eat grain and will starve to death unless fed their usual diet of grasses.
Most yaks are domesticated herd animals found in groups around the Himalayan region of southern Asia. Their vegetarian diet's digestion is aided by the animal's four-compartment stomach. Their waste is the primary source of fuel in the Tibetan plateaus. The animals are also raised to provide wool for clothing, as well as meat.