Bat wings are made of two thin layers of skin stretched over the bat's arm and fingers. Bats have a thumb and four fingers, just like people (sorry, you can only see 3 of the fingers in my photo -- it's tough to get a bat to pose!).
The bat's fingers are very long compared to its body. If we had fingers like a bat, they would be longer than our legs!
Bat wings go all the way down the side of the bat's body and partway down its legs.
When bats fly, they don't just flap up and down. If you watch them closely, it almost looks like they're pulling themselves through the air -- the movement is similar to the butterfly stroke in swimming.
Bats use their wings for more than just flying. They can wrap their wings around insects or fruit to hold it while eating.