Question for hairdressers, people who know about hair?

I recently got a job in Sally's Salon Services, and I know quite a bit about nails and waxing but nothing about hair. My manager told me not to worry as most people know exactly what they're looking for anyway, but hair dye confuses me. Could anyone explain to me the numbers, and the differences between peroxide etc, and toners? Thank you :)Question for hairdressers, people who know about hair?
The higher the number on the peroxide developer, the more lift you will get. 10 volume is no lift (from light to dyed dark hair), 20 is moderate lift (like going from light brown to dark blonde - best for most hair colors), 30 is high lift (going from medium brown to blonde) and 40 is high high lift, ( going from dark brown to blonde).








Semi and demi permanent are no-lift, you don't use any peroxide, the color just goes on the existing hair.