A steam car wash machine is a self-contained device that uses steam to clean a vehicle's exterior. The machine typically has a built-in water tank and boiler, and is connected to a water source and electricity. The operator starts the machine and steams the vehicle's surface. The steam loosens dirt and grime, which is then removed with a brush or cloth. Some machines also have a vacuum attachment to remove wet dirt and debris. Steam car wash machines are becoming increasingly popular as they offer a quick and easy way to clean a car's exterior without the use of harsh chemicals.