1. The outer ear: The pinna captures sound waves and directs them to the middle ear.
  2. The middle ear: The middle ear acts as an amplifier. The tympanic membrane (eardrum) vibrates like a drum, which then moves the ossicles—the smallest bones in the body.
  3. The inner ear: The cochlea translates the vibrations in the middle ear into electrical messages that the brain interprets as sounds.