Skin covers the entire body, and acts as a protective barrier. Scar tissue forms as skin heals after an injury (such as an accident) or surgery. The amount of scarring may be determined by the size, depth, and location of the wound; the age of the person; heredity; and skin characteristics including color (pigmentation). No scar can be removed completely. The degree of improvement will depend on variables such as the direction and size of the scar, the age of the person, skin type and color, and hereditary factors that may precondition the extent of the healing process.