cold sore or canker sore
Cold sores are a cluster of blisters that first appear clear then become cloudy. First infection may be inside the mouth, but cold sores generally appear outside the mouth on the lips. Canker sores are gray or white sores surrounded by a red inflamed area.old sores typically result from a viral infection called herpes simplex virus (HSV). Cold sore blisters can occur on many different parts of the body but are most common on or around the lips, cheeks, or nose and also (on rare occasions) in the eye.