Bats, like humans, are one of the few mammals that can fly.  Unlike humans, bats don’t ride in airplanes.  Bats have very long arms with creepy little claw-hands at the end.  These claw-hands have an extra strong grip so that they can hold open the stretchy sail-like piece of canvas bats use to fly.  When the canvas is not in use, or if a bat needs to dive suddenly to avoid a predator or catch an insect, the bat simply lets go of the canvas and it snaps back into the specially made pockets on either side of the bat’s abdomen.  This is why bats without hands cannot fly.