Scars come in all different shapes, sizes, and complexions. And the way they form largely depends on the individual and his or her skin type. Because different people have different skin types, the way scars form as part of the wound healing process can vary. Scars form in response to wounds attained from cuts, burns, piercings, tattoos, acne and surgical procedures. It’s difficult to predict what a person’s scar will look like even if we know the kind of wound she sustained. Two classifications of scars—keloid and hypertrophic—are common forms of scarring that can be unsightly, itchy, and even painful.