A viral infection causing lesions to the skin or mucous membrane. There are two types of the herpes simplex virus: type 1 (HSV), which usually results in the formation of cold sores, and type 2 (HSV2), which is usually sexually transmitted and causes genital sores to form. HSV2 is often more commonly refered to as genital herpes. Both HSV1 and HSV2, however, can result in formation of sores in other parts of the body.