A particularly dense covering, or coat, of hair is often referred to as fur. Throughout history, fur has been important to people, chiefly for warmth but also for decorative and other purposes. The pelts of fur-bearing animals are called true furs only if they consist of two elements: a dense undercoat (ground hair) and longer hairs (guard hair). Ground hair maintains the animal's body temperature and guard hair protects the underlying layer. Ponies do not possess ground hair, therefore, they do not have true fur.