How do we hear sound?

The Pinna for outer ear funnels sound vibrations into the ear canal. The sound waves hit the eardrum a thin layer of skin (membrane) at the end of the ear canal which vibrates. The vibrations move the ossicles, three small bones that make the sound louder. They send the sound waves to the cochlea. The cochlea is filled with fluid which ripples with the sound waves and move tiny hair shaped cells called cilia. Cilia transforms the vibrations into electrical impulses. The auditory nerve send these impulses to the brain, which translate the signals into the sounds you hear.