The Joy of Sex sold millions of copies within months of its publication in 1979. It was translated into 24 languages and ushered the sexual revolution into the mainstream with its graphic illustrations and playful treatment of sex as recreation. Hugely informative, it also dispelled shame, reassuring the public that everyone — your parents, your suburban neighbors — was doing it. The original text will seem old-fashioned to contemporary readers (it dismisses homosexuality, discusses “swinging” and refers to female partners as “girls”), but updated editions have added nearly 100 pages on topics ranging from safe sex to erectile dysfunction to gay partnerships. Which is one reason The Joy of Sex remains the living document of our bedroom behavior.