Facial hair is a seconary sex characteristic in human males. Many men develop facial hair in the later years of puberty, approximately between 15-18 years old although some men don't finish developing a fully adult beard until their early 20s or even later. This can vary, however, and males as young as 11 have been known to develop facial hair that require routine shaving. Further, many women also have some facial hair, especially after menopause, though typically much less than men.