Hair cells are specialized sensory cells found in the inner ear, crucial for hearing and balance. They have tiny hair-like structures called stereocilia on their surface, which move in response to sound waves or head movements. This movement triggers electrical signals that are sent to the brain, allowing us to perceive sound and maintain our balance. In addition to their role in hearing, hair cells are also present in the vestibular system, which helps the body understand its position in space. Damage to hair cells can lead to hearing loss or balance disorders, highlighting their importance in our sensory systems.