What is a hammer in your ear?

Three tiny bones (the smallest bones in the body) amplify the vibrations representing sound from the ear drum and transmit it across the eustacian tube (a cavity that opens into the thoat) to the cochlea. These bones are formally named the "malleus", the "incus", and the "stapes", but they are more commonly known as the "hammer", the "anvil" and the "stirrup".