Red is the rarest hair color, but to understand why that’s the case, you need a basic grasp of the science. There’s a lot more to it than the simple traits we learned about in high school biology.

Hair is a biological structure with amazing intricacy, not only a feature of your appearance or a statement of personal style ...

A hairstylist shares helpful hair advice for how to treat, prevent, and hide split ends. Check out the best products for breakage, best treatments, and more.