Ellen Says:--A hairstyle, hairdo, or haircut refers to the styling of hair, usually on the human head.
The fashioning of hair can be considered an aspect of personal grooming, fashion, and cosmetics, although practical, cultural, and popular considerations also influence some hairstyles.
A hairstyle's aesthetic considerations may be determined by many factors, such as the subject's physical attributes and desired self-image or the stylist's artistic instincts.
Physical factors include natural hair type and growth pattern, face and head shape from various angles, and overall body proportions; medical considerations may also apply.
Self-image may be directed toward conforming to mainstream values (military-style crew cuts or current "fad" hairstyles such as the Dido flip), identifying with distinctively-groomed subgroups (e.g., punk hair), or obeying religious dictates (e.g., Orthodox Jewish have payot ,Rastafari have Dreadlocks or the Sikh practice of Kesh , though this is highly contextual and a "mainstream" look in one setting may be limited to a "subgroup" in another.
This may include what has best been deemed "The Helmet Head", most recently re-popularized by Canadian teen heartthrob, Justin Bieber.