A scab is a hard, dried blood clot that forms over a cut or broken skin to stop bleeding and protect the underlying tissues from germs during the healing process
. It acts as a natural shield, preventing infection and allowing new skin cells to grow underneath. Scabs form when blood platelets clump together and are held by fibrin, a protein that creates a fibrous net to keep the clot in place; as the clot dries and hardens, it becomes a scab
. Scabs usually appear crusty and dark red or brown and remain firmly attached until the skin beneath has healed sufficiently, after which the scab falls off naturally
. While scabs protect wounds, keeping the wound moist with petroleum jelly and covering it can sometimes speed healing and reduce scarring compared to letting a scab form
. In summary, a scab is the body's protective covering over a wound, formed by dried blood and clotting factors, essential for wound healing and infection prevention
