Old Steam Trucks

Almost all trucks share a common construction: they are made of a chassis, a cab, an area for placing cargo or equipment, axles, suspension and roadwheels, an engine and a drivetrain. Pneumatic, hydraulic, water, and electrical systems may also be identified. Many also tow one or more trailers or semi-trailers.
• Cab
The cab is an enclosed space where the driver is seated. A "sleeper" is a compartment attached to the cab where the driver can rest while not driving, sometimes seen in semi-trailer trucks.