A sheep and a lamb are both members of the same species, but they are not the same animal. A lamb is a young sheep, typically one that is less than one year old. Lambs are born with wool and a distinct lamb-like face. Sheep, on the other hand, are usually over one year old and have a more mature appearance. Sheep are also usually larger than lambs and have horns. Lambs are typically bred for meat while sheep are bred for wool and milk.