Ear
The ear is the part of the body which allows animals (including people) to hear. People and most mammals have ears. Non-mammals, such as lizards or frogs, can also hear, but may have holes instead of external ears. The ear works by directing sound waves to the inner ear. These vibrations are sent to the brain by an organized group of nerves. This system is called the auditory system. (Auditory meaning relating to hearing and how we hear)