Tank
Most modern tanks most often have four crew members, or three if an auto-loader is installed. These are the:
Historically, crews have varied from just two members to a dozen. For example, pre-World War II French tanks were noted for having a two-man crew, in which the overworked commander had to load and fire the gun in addition to commanding the tank. First World War tanks were developed with immature technologies; in addition to the crew needed to man the multiple guns and machine guns, up to four crewmen were needed to drive the tank: the driver, acting as the vehicle commander and manning the brakes, drove via orders to his gears-men; a co-driver operated the gearbox and throttle; and two gears-men, one on each track, steered by setting one side or the other to idle, allowing the track on the other side to slew the tank to one side.
Panzer II
The Panzer II had a crew of three men. The driver sat in the forward left hull with the gearbox on the right. The commander sat in a seat in the turret, and was responsible for aiming and firing the cannon and co-axial machine gun, while a loader/radio operator sat on the floor of the tank behind the driver. He had a radio on the left and several 20mm ammunition storage bins.