Mammals cannot fly in general, but there is an exception. And no, it’s not Superman.
Bats are mammals whose forelimbs form webbed wings. This makes them the only mammals that are naturally capable of having true and sustained flight. There are other mammals that can fly such as flying squirrels and gliding possums, but they can glide only for short distances.
The bat’s body is suited for flying. It is stubby as well as streamlined with the chest broader than its tail. Its body is light and its wings can be folded between strokes of flight, making the bat more aerodynamic. In essence, bats “row” their wings and create lift. This allows bats to hover as well as move in all directions.