There are three different types of hearing loss; sensorinueral, conductive or mixed.
Sensorineural: When hair cells inside the cochlea die. The cochlea is attached to the nerve of hearing which communicates to your brain.
Conductive: When something mechanical doesn’t work in the inner ear. Could be a perferrated tympanic membrane (punctured ear drum) or ossification of the ossicular chaine (three smallest bones in your body; Incus, Malleus and Stapes).
Mixed: A combonation of the two types of hearing loss.