Acne is a disease of sebaceous glands due to chronic inflammation which cause skin eruption, redness, and pustule. Acne is most common among people who have oily type of skin. People with dry type of skin do not generally suffer from acne and if they do suffer, the acne among people with dry type of skin is of milder type.

The most common site where acne occurs is the face. But acne can occur in any parts of the body where there is pilosebaceous gland in the skin such as trunk, scalp and limbs. Acne occurring in the trunk is called body acne or trunk acne. The only parts of the body where acne does not occur are palms and soles as these parts of the body do not contain any pilosebaceous glands.