You may have read in the news over the past few days about the passing of Carl Djerassi, the chemist (and later, novelist) who is best known for his discovery of the first oral contraceptive. This discovery led to something of a social revolution, putting the power of contraception firmly in the hands of women, as well as changing sexual attitudes. This graphic looks at the some of the common chemicals used in oral contraceptives, and how they work.