司机，现多指汽车司机，亦可称「驾驶员」，是指驾驶和控制车辆的人，包括路面车辆和铁路车辆在内。

司机可以分为职业司机、车主或其亲友借车暂用，还有是出租车司机、代客泊车多种，虽然皆为驾驶车辆，但是社会阶级非常不同。

司机对路面行人及第三者都有职业道德。有一些法例管制司机的不当行为，例如驾大胆车、顶包、交通意外后不顾而去、鲁莽驾驶、酒后驾驶等。

A chauffeur is a man employed to drive a passenger motor vehicle, especially a luxury vehicle such as a large sedan or limousine. A woman employed to drive a passenger motor vehicle is a chauffeuse.

Originally, such drivers were often personal employees of the vehicle owner, but now in many cases specialist chauffeur service companies or individual drivers provide both driver and vehicle for hire, although there are service companies that just provide the driver.