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.
The chemicals in a perm cause the hair shafts to open. This leaves the hair porous, and porous hair is perfect for the coloring process. The hair color takes less time to absorb, and less time on the hair means less damage to the hair. Make sure to only use semi-permanent or demi-permanent hair colors after a perm.