The main difference between a two-hump camel (Bactrian camel) and a one-hump camel (Dromedary camel) is the number of humps on their backs. Bactrian camels have two humps, while Dromedary camels have one hump. Additionally, Bactrian camels are found in Central Asia and have thicker fur to withstand colder temperatures, while Dromedary camels are found in the Middle East and North Africa and are adapted to hot desert climates.