Hair transplantation is simply the transferring of hair from a "permanent" area of the scalp to another area in which hair has fallen out due to heredity or some other more unusual cause. For most men and women who lose the hair on the top of their head, the hair on the back and sides of their head is relatively thick and destined to remain there for the rest of their lives. This "permanent" hair is harvested in the form of a narrow "strip" of hair, which is then meticulously cut up under microscopic magnification to produce hundreds of tiny follicular unit grafts of 1-3 hairs each, and also, in some sessions, small “multi-FU grafts” of 2 or 3 adjacent follicular units.