What forms a scar?

Scar tissue is the fibrous connective tissue which forms a scar; it can be found on any tissue on the body, including skin and internal organs, where an injury, cut, surgery or disease has taken place, and then healed. Thicker than the surrounding tissue, scar tissue is paler and denser because it has a limited blood supply; although it takes the place of damaged or destroyed tissue, it is limited in function, including movement, circulation, and sensation. Other than with minor cuts and scrapes, scarring is a common result of any bodily damage.

Scar tissue in the skin is inferior to healthy, normal skin for several reasons: sweat glands are damaged or destroyed, hair does not grow back, and there is less resistance to ultraviolet radiation