TECHNIC is one of The LEGO Company's main lines based on creating detailed model machines and mechanical toys with specialized beams, axles, gears and connectors and primarily designed for older children and adults. The theme was first introduced as the Expert Builder series in 1977, but was officially renamed as TECHNIC in 1984. TECHNIC is still an active theme, and is one of the longest running themes in LEGO history. While most TECHNIC sets are vehicles that use pieces to mimic real vehicles, such as engine pieces, suspension, pneumatic, and transmission pieces, the TECHNIC parts have been used by various other System themes as well as LEGO Mindstorms.