Heat lamps are similar to regular incandescent lamps (see below) but produce higher levels of infrared radiation. This creates more radiant heat, proving to be more useful as a source of warmth than a regular lamp. There are two kinds of heat lamps, red lamps and frosted/clear lamps. They function identically in terms of heat production, but the red lamp is designed to produce less visible light. Heat lamps are widely used in foodservice to prevent freshly prepared, hot dishes from cooling down before being delivered to the customer.