The process by which tissue that has been damaged through an injury is repaired. Wound healing is a biological process that can be speeded up or aided by surgical intervention.

A wound that is surgically closed is said to heal through primary intention. Wounds can be surgically closed with sutures, staples or tissue glue.

A wound that is more than 8 hours old, infected or has loss of tissue preventing full surgical repair is said to heal by secondary intention. The tissue repair (granulation) takes place from the inside out, i.e., from the deepest part of the wound toward the surface.