Surgery is a medical specialty that uses operative manual and instrumental techniques on a person to investigate or treat a pathological condition such as a disease or injury, to help improve bodily function or appearance or to repair unwanted ruptured areas.
Wound closure is final step of surgical procedure. Wound closure involves the closing of Skin at the end of surgical intervention. Wound length may vary according to the surgery. There are three main layers of the skin.
Epidermis is the top layer of the skin, the part of the skin you see.  Dermis is the second layer of skin. It's much thicker and does a lot for your body.  Subcutaneous fat is the bottom layer.