Without color; lacking characteristics which give variety. blank (Adjective). Free from writing, printing, or marks; having an empty space to be filled in; as, blank paper; a blank check; a blank ballot. blank (Adjective). Without expression.
Yes they do damage hair. Every time I have tried one ,I wound up looking like a Q-tip or my head looked like cotton. A perm will damage even more and look worse if you have been coloring your hair. There's chance of it looking okay if you don't color your hair.
Although new hair growth will be a factor after a couple of months, perms can last for up to six months with gentle care and treatment. To make a perm last longer, avoid heat styling as much as possible. Use a hair-dryer diffuser to help retain the curl of the perm and soften the damage of heat styling.