The LEGO DUPLO theme is designed for children ages 1 to 5. It features DUPLO figures which are much larger than minifigures and DUPLO blocks which are about twice the length, width, and height of a standard System brick.
1978 LEGO Sets
In 1978, LEGO released several new sets and themes, including the LEGO City theme, which expanded upon the city sets released in previous years and introduced new models of public transportation such as buses and taxis.