Milia are very common, benign, keratin-filled cysts (see the image below).
Milia in a week-old infant.
Primary milia are typically seen in infants but also may occur in children and adults. Secondary milia develop after trauma to the skin, such as after burns (eg, sunburns), dermabrasion, or in blistering disorders. Milia en plaque is a rare inflammatory condition characterized by plaques of milia in the periauricular area. Multiple eruptive milia is a condition characterized by the sudden development of crops of milia over the course of weeks to months.