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 not as dangerous as perming highlighted hair, if your hair is colored, you may want to give more thought to a perm. It will be in your best interest to allow 2- 3 weeks before and after your perm to color your hair. Also, keep in mind that a perm will likely lighten your color.