Bats use echolocation to navigate and hunt at night. They produce ultrasounds, frequencies above the range of human hearing, and can hear the echoes when the sounds bounce off objects. This allows bats to detect obstacles, prey, and navigate while flying even in darkness. Bats are divided into microbats and megabats and are found worldwide except at the poles. They emit ultrasounds from their mouth and can hear the vibrations that return from nearby objects as they fly.