Acne is inflammation of the skin, due to blockage of your skin’s pores. Blockage occurs due to an excessive secretion from the skin’s oil glands and accumulated, dead skin cells. This combination encourages the skin bacterium Propionibacterium which multiplies and causes increased skin inflammation. Acne comes from the Greek word, άκμή or acme, meaning skin eruption. Common acne is acne vulgaris.