We are able to receive messages, which come to us from the outside world through our senses. Our ear has a sense of hearing which enable us to distinguish between wide range of tones and sounds.
The sound waves are collected by the auricle (outer ear) causing the drum (thin/taut membrane) to vibrate. This vibration produces movements of tiny bones of the middle ear (hammer, anvil, stirrup).
The stirrup transmits the vibrations to a special fluid in the inner ear which are then passed on to the cochlea containing semicircular canals; the main organ of hearing.
These canals are connected to the brain and enable us to keep our balance and stand up right. The sound is finally transmitted to the brain by the acoustic nerve.
Below Hearing info from Wikipedia (Read More):-
Hearing (or audition) is one of the traditional five senses. It is the ability to perceive sound by detecting vibrations via an organ such as the ear. The inability to hear is called deafness.
In humans and other vertebrates, hearing is performed primarily by the auditory system: vibrations are detected by the ear and transduced into nerve impulses that are perceived by the brain (primarily in the temporal lobe). Like touch, audition requires sensitivity to the movement of molecules in the world outside the organism. Both hearing and touch are types of mechanosensation.
http://en.wikipedia.org/wiki/Hearing_%28sense%29
