Bats are a very numerous and diverse group of animals and can be found all over the world. They are also the world's only mammal which can fly under its own power. Their ability to fly can be very helpful to them because it helps them move quickly and travel long distances. Bats usually only come out at night and have very small eyes which has often led to the myth that bats are blind. Bats can see very well, although we don't know how much bats rely on their sight because they would rather use echolocation to get around.
Echolocation is sort of like radar or sonar.
The bat makes sounds that are very high pitched. These sounds are so high pitched that humans can't hear them. As the sounds bounce off objects it creates an echo. The bat then listens for the echo to return. By listening to where the echo comes from, the bat can avoid obstacles in its path or locate some juicy bug to eat.