During World War II most toy factories were turned over to war production. However in the late 20th century with the arrival of an affluent society plastic and metal toys became much cheaper and much more common. In the 1950s Lego became a popular toy. Mr Potato Head was invented in 1952. The skateboard was invented in 1958. Barbie dolls were invented in 1959 and Action Man went on sale in Britain in 1966. In the early 1970s space hoppers and clackers were popular toys. At the end of the 20th century computer games became very popular.