The anatomy of the ear is divided into three sections: the outer ear, middle ear, and inner ear. The outer ear is sometimes called the external ear. The external ear is the part of the ear that can be seen in a mirror and the ear canal. The purpose of the external ear is to direct sound to the tympanic membrane, also called the eardrum. The eardrum produces vibrations in accordance to the sound.

The middle ear is a collection of bony structures that sit in an air-filled cavity behind the eardrum. These tiny structures are called the stirrup, hammer, and anvil. Collectively, they are referred to as ossicles. Together they transmit the vibrations of the eardrum to the inner ear. The Eustachian tube periodically opens and closes to maintain the proper air pressure in the middle ear.

The structure of the inner ear is sometimes referred to as a bony labyrinth or osseous labyrinth. The inside the bony labyrinth is called the membranous labyrinth. The membranous labyrinth contains fluid and structures necessary for the perception of sound.

The cochlea and the auditory nerve are crucial parts of the inner ear. The cochlea processes the vibrations and translates them to messages that can be sent by the auditory nerve. Receptor cells in the inner ear transmit nerve signals to the auditory nerve. The auditory nerve, called the eighth nerve, transmits the sound messages to the brain for processing.

Problems with the anatomy of the ear can result in hearing loss or deafness. Blockage of the ear canal or a malfunction of the structures of the middle ear can stop the passage of sound to the inner ear. The blockage of sound to the inner ear causes conductive hearing loss. In many cases, conductive hearing loss can be medically treated to remove the cause of the blockage or surgically correct problems with the middle ear.

Problems with the functions of the inner ear can cause sensorineural hearing loss. Sensorineural hearing loss cannot be surgically or medically corrected and is considered permanent hearing loss. Common treatment of sensorineural hearing loss is the use of hearing aids.