Hair transplantation is an artistic, surgical redistribution of the permanent/ lifelong hair follicles taken from the donor dominant areas, viz., the back and sides of the head to the bald/balding areas of the scalp.
These long life hair follicles/roots are transplanted into the bald/balding areas of the scalp. With current microsurgical technologies, this results in a very natural appearing hair regrowth in the bald scalp areas. Just enough hair follicles are taken from the back and sides of the scalp so as to leave behind sufficient hair in the donor areas.
These transplanted hair keep growing for the rest of person's life. You can cut them or shave them. They will grow back on their own without need of any medicines or special aftercare.