Magnet wire is an insulated copper or aluminum conductor used to wrap around motors, transformers, generators, and any other electrical equipment that converts electrical energy into mechanical energy. The insulating layer may be a varnish film or some type of cover layer such as polyester glass, mica, or polyimide tape.

Insulation provides electrical or mechanical properties to the wire. Winding wire is another name for magnet wire. Winding wire is commonly used in Europe and Asia, while the enameled wire is used more in North America.

Insulation is the amount of enamel or covering added to the circumference of the wire. Enamel is available in four different insulating constructions: single, heavy, triple, and quadruple. There are many build variants available for other product lines. The insulating structure is directly related to the required dielectric strength or the required degree of mechanical protection.