The game of Spirograph was invented by Denys Fisher, a British electrical engineer working for NATO on a new design for bomb detonation! Fisher was fascinated with hypocycloids, defined as "a curve traced by a point on the circumference of a circle that rolls without slipping on the inside of a fixed circle." It was subsequently produced by his company but distribution rights were acquired by Kenner Inc., which introduced it to the American market in 1966, promoting it as a creative children's toy. Spirograph was an immediate success?over 5.5 million kits were sold in two years, making it one of Kenner's top toys of the late 1960s. Sometimes ideas come from the strangest places!