The parts of the ear that enable hearing are the outer ear, middle ear, and inner ear, and the auditory nerve: 

• Outer ear: Sound waves enter the ear through the ear canal and hit the eardrum. 
• Middle ear: The eardrum vibrates and sends vibrations to the malleus, incus, and stapes, three tiny bones that amplify the sound vibrations. 
• Inner ear: The vibrations are sent to the cochlea, a snail-shaped organ that contains fluid and hair cells. The vibrations cause the fluid to ripple, which moves the hair cells. The hair cells bend, which opens pore-like channels that send an electrical signal to the brain via the auditory nerve. The brain interprets the electrical signal as sound. 
• Auditory nerve: Carries the electrical signal from the inner ear to the brain.