Herpes simplex (from the Greek ἕρπης /΄erpis/, "snake") is a viral disease caused by herpes simplex viruses; both herpes simplex virus 1 (HSV-1) and herpes simplex virus 2 (HSV-2) cause herpes simplex. Infection with the herpes virus is categorized into one of several distinct disorders based on the site of infection. Oral herpes, the visible symptoms of which are colloquially calledcold sores, infects the face and mouth. Oral herpes is the most common form of infection. Genital herpes, commonly known simply as herpes, is the second most common form of herpes. Other disorders such as herpetic whitlow, herpes gladiatorum, ocular herpes (keratitis), cerebral herpes infection encephalitis, Mollaret's meningitis, neonatal herpes, and possibly Bell's palsy are all caused by herpes simplex viruses.