Bats are nocturnal animals that come out at night to feed. Most live in caves, where they breed and sleep. Maybe this is why some people are afraid of them. Bats have been featured in many horror movies as terrible blood-sucking monsters that track down people to feed on their blood.
Bats have large, leathery wings. The wings are tipped with five pointed 'fingers'. The fingers allow the bat to cling to objects, like a tree trunk or building. The bat also have large, sensitive ears that play a role in echolocaton to find their prey. The bats use this by sending out a sound wave. The waves will bounce off another object, then back to the bat's ears.
Bats are not really the monsters many people are afraid of. In fact, they rarely bother people at all! Most bats live on insects, like mosquitoes, that come out at night. A few exotic bats live on fruit. The vampire bat sucks the blood of an victim, such as a cow, for a short while before letting go and fluttering away.
When vampire bats do occasionally feed on people, the bat feeds like it normaly does. The victim may not even realize that they have been bitten until they wake up. The bats do not carry parasites, but they may have rabies.
Bats are wonderful creatures. They keep the ecosystem in check. Without them, there would be more mosquitoes and diseases. So bats are doing us a big favor! All bats are peaceful in a odd sort of way, and without them maintaining the environment, it would never be the same.