The vermilion border (sometimes spelled vermillion border), also called margin or zone, is the normally sharp demarcation between the lip and the adjacent normal skin. It is where lipstick is sometimes applied. It represents the change in the epidermis from highly keratinized external skin to less keratinized internal skin. It has no sebaceous glands, sweat glands, or facial hair. It has a prominence on the face, creating a focus for cosmetics and is also a location for several skin diseases. Its functional properties, however, remain unknown.