Bats can use sonar to see in the dark, locate food and find their homes but bats aren't the only animals who use sonar moles, birds and even humans use sonar. Soldiers used bats and birds to make bombs, one of the bombs was filled with bats that had a small incendiary attached to them the bats were trained to go attach themselves to a house than the bomb would detonate and the house would blow up or set on fire.

Sonar is used a lot these days for example we use sonar: In airplanes to detect other planes, for hunting, video cameras and tracking devices

Sonar changed WWII because the Nazis and the Americans could detect each other's movement sonar is very valuable today because it helps us find phones, places and even children. In 1906, American naval architect Lewis Nixon invented the first sonar-like listening device to detect icebergs. During World War I (1914-18), a need to detect submarines increased interest in sonar. French physicist Paul Langévin constructed the first sonar set to detect submarines in 1915.