A squirrel cage is a cylindrical device typically found in electrical motors and generators. It consists of a series of bars or conductive elements arranged in a circular fashion, resembling the shape of a cage. When an electric current is applied, it creates a rotating magnetic field, which interacts with the conductive bars to generate mechanical motion or induce voltage. The term "squirrel cage" refers to the resemblance of this arrangement to a cage that could potentially house a squirrel.