A hair primer is a leave-in conditioning treatment applied to damp or dry hair before styling. Like a face primer, it provides a base for hair products to better adhere and perform.
Hair primers offer several benefits, including detangling, smoothing, and protection against heat damage. They can also enhance the hold of hairspray and volumizers. Historically, hair primers were primarily used by professionals, but they have become increasingly popular for home use due to advancements in hair care technology.