The permanent wave, called a perm, is a popular hair treatment that makes the hair curly and wavy. The perm lasts until the your hair grows out completely.
A hairdresser from Germany named Charles Nessler developed the very first perm in 1905. It consisted of hot curlers and Borax (sodium borate), a natural household cleaner.
Nessler was described as a "hair scientist." He studied the hair of over 100,000 people and invented the Hair Kerascope, a tool that measured the denseness of hair follicles.
Nessler studied Caucasian hair in particular, and classified it into different types according to its elasticity and ability to absorb fluids.
The very first perms took 12 hours to complete and cost the client hundreds of dollars.
Relaxers for ethnic hair, which are often called "perms" and make the hair straight, were developed by an inventor named Garret Augustus Morgan by accident. He wiped chemicals from another project onto a wool cloth and then returned to find the fibers straight.