Wound healing is the process by which your skin or other body tissue repairs itself after trauma. In undamaged skin, the epidermis (surface layer) and dermis (deeper layer) form a protective barrier against the external environment. When the barrier breaks, biochemical events/process in phased manner—blood clotting, inflammation, tissue growth, tissue remodeling—take place.
Some people are prone to wounds; for some, wounds take long time to heal. Hence, never leave any wound unattended; take good care of it.