Acne is a skin problem. It happens when the skin gets clogged with oil, which causes pimples.
Most teenagers get acne.
During these years, hormones cause more body hair to grow and the skin gets oilier. The skin pores sometimes get clogged with oil and bacteria. In very bad cases, you may get a cyst. A cyst is a bump that forms under the skin. It is larger than a pimple.