It's a 'high density' foam, which moulds itself to the ear canal. The density of the foam, coupled with the snug fit in the ear, limits the volume of sound reaching the eardrum.
you can put head phones in or ear muffs or you could just not the loud sound in the first place
To protect their ears and hearing from getting damaged by loud noises.
No you will not loose you your hearing but your ear will get infected because the hairs are their to protect it, and when you ear gets infected it could get damaged badly, so then you may loose your hearing.
A soft case will protect a camera from being damaged if it were to fall. It can also protect sensitive lenses from scratches.
Earmuffs used for cold temperatures protect your ears, by keeping them warm. Because ears are sticking out from the rest of your body, they are susceptible to being damaged from frost-bite, and in severe cases, could even fall off. Earmuffs used for sound protect your ears from loud noises, that could burst your eardrum and/or make you deaf.
The ear drum.
anything
Sheating conductor is the material that wraps wires to protect you from shock and the wire from being damaged.
Ear defenders protect your ears by absorbing the sound and fizzling it out
You can damage the tympanic membrane (ear drum).
the eardrum