There are two types of camel - the one-humped Arabian camel and the two-humped Bactrian camel. Both are well equipped for desert life. A camel's hump can weigh up to 13.5 kg (30 lb) and contains fat which can be used when there is no food. Camels can survive for many days without food and water. After a drought they will drink up to 114 litres (25 gallons) of water in one go.