An icemaker, ice generator, or ice machine may refer to either a consumer device for making ice, found inside a home freezer; a stand-alone appliance for making ice, or an industrial machine for making ice on a large scale. The term "ice machine" usually refers to the stand-alone appliance.Ice machines work to produce a batch of ice through a process known as adiabatic cooling. When a highly pressurized substance expands, the change in pressure causes the substance to cool quickly. It's the same reason why the pressurized air you use to clean your keyboard becomes cold when you hold down the trigger.