They are flying mammals, bats, easily recognized but much maligned, and poorly understood. For many humans, bats evoke fear and repulsion based on fable, myth and ignorance.
Bats are a distinct group with more members than any other mammal assemblage except rodents.
Like other mammals, including humans, bats possess hair, milk glands, and give live birth. Unlike other mammals, they have wings and are capable of true flight. Their wings are formed by a double layer of skin stretched over the arm and elongated fingers. The membrane also extends to the hind legs and, in most species, between the legs and connecting with the tail. These membranes are not only used for flying, but also as a scoop for capturing insects in flight.