The easiest way to describe a bat is to say it looks like a mouse with wings. With smaller eyes, large ears and larger mouths full of teeth, they look fiercer than mice.
Bats are the only mammals that truly fly.
Other so-called flying mammals, such as flying squirrels, actually glide. Although the wings are often hairless and even transparent in places, the body of the bat is covered with soft fur. Bat wings are made of greatly lengthened hand and arm bones covered by a wide membrane or skin. The skin is attached to the lower leg near the ankle so that the wing is almost as wide as the bat's body is long, from nose to toes. Using powerful muscles, the bat doesn't just flap its wings up and down like a bird.