Introduction: Acne is a skin condition that causes whiteheads, blackheads, and inflamed red growths (papules, pustules, and cysts) to form. Pimples, Blackheads and Bumps are Typical of Acne A pimple, zit or spot is a kind of acne, and one of the many results of excess oil getting trapped in the pores. Acne is a common skin disease that causes pimples. Pimples form when hair follicles under your skin clog up. Most pimples form on the face, neck, back, chest and shoulders. Anyone can get acne, but it is common in teenagers and young adults. It is not serious, but it can cause scares. BLACKHEAD:A familiar term for what is medically called an open comedo. A comedo, the primary sign of acne, consists of a dilated (widened) hair follicle filled with keratin squamae (skin debris), bacteria, and sebum (oil). WHITEHEAD: A familiar term for what is medically called a closed comedo. It is a comedo that has an obstructed opening to the skin. A closed comedo may rupture ...