What chemical service is the term "perm" short for?

The term "perm" is short for "permanent wave," which refers to a chemical treatment used to alter the structure of the hair, creating waves or curls that last for an extended period. This process involves the use of a chemical solution that breaks down the disulfide bonds in the hair, allowing it to be reshaped around rods or curlers. Once the hair is set in the desired shape, a neutralizer is applied to reform the bonds in their new configuration, resulting in long-lasting waves or curls.

Understanding this concept is crucial for hairdressers, as it highlights the significance of chemical bonds in hairstyling and the precise techniques needed to achieve desired outcomes while ensuring hair health. The other choices describe different services that do not involve creating curls or waves with a chemical process.