Our sense of hearing, which allows us to receive and interpret sounds, is an amazing system. It is a complex process, not yet fully understood my modern science. 

The ear (known as the outer pinna) directs sound waves down the auditory canal to the eardrum (known as the tympanic membrane), causing it to vibrate very slightly. The ossicles in the middle ear are the three smallest bones in the human body, and consist of the hammer (malleus), anvil (incus) and stirrup (stapes). They work as a lever system to amplify the vibrations, which are then passed along to a smaller vibrating membrane (known as the elliptical window) on the surface of the cochlea of the inner ear.

The mechanical energy of the sound, now translated to a physical vibration, creates compression waves within the fluid-filled spiral tube of the cochlea, which in turn move the tiny hair cells lining the inside of the cochlea. As the hairs move, nerve cells at their base change this motion into electrical signals that are passed along the auditory nerve to the central auditory processing centres of the brain, where the signals are interpreted as recognizable sound.