Plastic surgery is a surgical specialty involving the restoration, reconstruction, or alteration of the human body. It can be divided into two categories. The first is reconstructive surgery which includes craniofacial surgery , hand surgery , microsurgery , and the treatment of burns . The other is cosmetic or aesthetic surgery. While reconstructive surgery aims to reconstruct a part of the body or improve its functioning, cosmetic surgery aims at improving the appearance of it. Both of these techniques are used throughout the world.