How does hearing aid help people with hearing problems?

Please give me exact answers. Tnx

Actually, there are two kinds of hearing aids -- traditional, and bone conduction, and they work very differently. Traditional hearing aids work through amplification, that is, making the sound louder. Newer digital hearing aids then digitally process that louder sound in an attempt to filter out background noise and make it sound more like natural sound and less "tinny." These are the types of hearing aids you wear when you have a problem with your auditory nerve.

Bone conduction hearing aids work by routing the sound to the cochlear nerve through the skull, bypassing the anatomical deformity that is blocking the sound from getting to the nerve.

It increases the resonance of the ear; by making the acoustics that come through your ear; (auditory canal); resonate on your tympanic membrane; it probably uses advanced acoustic resonating equipment; like magnets, computer chips, whatsoever.
Hearing aides amplify the sound in the ear canal.
I don't really know. I spent $5200.00 on a pair and they spent more time in the shop than they did in my ear. The warranty ran out and I didn't get much use out of them. The insurance company will only bye one pair in a life time. So I guess I am out of luck as for as my hearing goes for the rest of my life. The batteries for the aids are not cheap either and they don't last but a few days either. Wouldn't own another pair if they were given to me.