The inner ear is the innermost part of the vertebrate ear, near the base of the skull, hidden in the hard bone. The inner ear is primarily responsible for sound perception and balance. The inner ear, also called the vestibule, is usually composed of a bony vestibule and a membrane vestibule and has two main systems: the cochlea: converts sound pressure patterns from the outer ear into electrochemical impulses that are transmitted to the brain through the auditory nerve and is responsible for hearing; and the vestibular system: is responsible for sensing body movements and maintaining body balance and is responsible for balance. The bony vagus is composed of three parts: the vestibule, the semicircular canal and the cochlea. The vestibule is the central part of the bony vestibule and is responsible for the perception of horizontal and vertical body movements; the bony semicircular canal has three semicircular canals, the lateral semicircular canal, the superior semicircular canal and the posterior semicircular canal, which are responsible for the perception of rotational body movements; the cochlea is shaped like a snail and is responsible for the conversion of sound signals into electrical signals. Inner ear disorders can be caused by a variety of reasons, and inner ear disorders can cause patients to experience ear discomfort, a sense of occlusion, ear swelling and fullness, pain, tinnitus, hearing loss, vertigo and other symptoms, usually due to trauma and infection. Problems in the inner ear generally indicate more serious pathologies in the body’s hearing system, and require seeking medical help as soon as possible.