Building Sets are the plain DUPLO brick sets, buckets and boxes of bricks without a story. DUPLO started in 1969, and the name comes from the Latin word for double, because each brick is twice as long, wide and high as a LEGO brick. The studs are made to fit, so DUPLO and LEGO bricks lock together and a builder can move from one to the other. For years the plastic bucket was the usual way to sell them, from the 1980s through the early 2000s, often shaped or printed as an animal, a farm or a circus, and some came as anniversary editions. Later sets switched to cardboard brick boxes with ideas for what to build on the side.
1987 LEGO Sets
1987 reshaped core worlds: Futuron and Blacktron established a new Space rivalry, and the Forestmen arrived in Castle with woodland hideouts and outlaw flair. Early computer-control experiments appeared in the Technic ecosystem, foreshadowing later programmable systems. Across the portfolio, factions and clearer narratives became a defining design focus.