You need to understand how Hair Grows? However our hair consists of four main organs:

Follicle - the hair canal
Papilla - the organ that feeds hair growth
Sebaceous Gland - the associated oil gland
Hair - shaft or structure which has hardened (keratinized)

Follicle

A hair follicle is an important part of the skin. Each follicle is just like the skin's surface being an inward fold into the skin for producing a hair. The lower portion of the follicle has an expanded shape and is called the follicle bulb where there is an area of actively dividing cells called the hair matrix. This is the source of hair production. The follicle and the hair it produces continue through repeated cycles of growth and rest.

Papilla

Papilla is the skin-related cells which feeds the hair cells from its blood supply at the base of the follicle lies as a tiny structure. With a hardened or keratinized structure like the hair shaft, the new born hair cell grows and dies constantly and continuously. The hair shaft continues to grow outward from the follicle base.

Sebaceous Gland

The sebaceous glands or oil glands are placed under the surface of the skin all over the body. Large number of these sebaceous glands or oil glands can be found in the facial area. The oily material secreted is called sebum. Sebum lubricates the hair shaft and the skin.

Hair

The papillary region is known as the "hair root". Hair is originated in this region below the surface of the skin which is contained within the follicle canal. The hair shaft is grows above the skin surface. There are two types of hair formed by the follicle such as vellus and terminal.

Generally Vellus hair can be found on a woman's cheek or a young child just like "peach fuzz".y. It is soft and colorless. The follicles producing vellus hair are shallow, and the hair shaft produced is relatively short. Terminal hair is deeply rooted, coarse, and colored. Terminal hair begins as the peach fuzz type but later develops color and some degree of coarseness at which point it becomes the terminal type. Terminal hair grows from the scalp, eyebrows, underarms, pubic area, and other parts of the body.