Monocoque construction is where there is no separate chassis - the chassis and body of the car are combined in a single unit known as a bodyshell.

Early cars usually used separate chassis frames, but monocoque construction began to take over in the 1950s. Today almost all cars are monocoques, though 4x4s and light commercials sometimes retain separate chassis and some specialised vehicles (for example, using lightweight aluminium or composite bodywork) may have separate chassis.