A scar reflects how wounded skin heals. Wound healing is a dynamic process that involves the three overlapping phases of inflammation, granulation tissue formation and remodelling. The relative importance of these steps depends on the depth of tissue loss. Partial thickness wounds which involve only the epidermis and superficial dermis without damage to skin appendages such as hair follicles, sweat glands and sebaceous glands tend to heal with minimal or no scarring although pigment changes sometimes occur. Full thickness wounds which involve the deep dermis heal with scarring. Initially there is clot formation to halt bleeding from damaged blood vessels followed by inflammation and granulation. Contraction allows the edges of the wound to come together with scar tissue forming to replace the tissue loss.