During normal hearing, sound waves travel through the ear canal and strike the eardrum causing it to vibrate. The eardrum is attached to three tiny bones in the middle ear. The last bone, the stapes, pushes on a fluid-filled chamber in the inner ear, called the cochlea.
This fluid movement causes sensitive hair cells within the cochlea to bend. When the hair cells bend, they generate an electrical signal that is sent to the brain.
The eardrum and the inner ear can be damaged by a sudden loud sound like an explosion or jet engine. Or they can equally be damaged over time by continuous levels of damaging sound, like listening to music at a high volume through an earpiece or headset.
This repeated exposure to loud noise can damage the various structures of the ear and interfere with hearing.
Sadly, much of hearing loss is preventable and a little prevention can assure you never risk suffering from noise-induced hearing loss.