Electrical resistance heating is an efficient way of applying heat directly to the surfaces requiring it. Also referred to as Joule heating, such devices can take many forms. Printed conductive inks and pastes present a versatile approach to apply heater patterns and electronic circuitry onto a variety of substrates materials like metals, textile fabrics, rigid and stretchable polymer films, leather and many more. Providing uniform heating power over a large area efficiently directs the heat to the intended surface without the need for heat spreaders or padding to prevent the heater being seen or felt. The heating elements can be printed with fixed resistance pastes, or positive temperature coefficient of resistance (PTC) paste can be used to reduce power as operating temperature is achieved and to reduce overall power consumption.