LED stands for Light Emitting Diode. An LED is a silicon semiconductor that lights up when current passes through the circuit. LED lights are significantly more efficient than traditional incandescent globes as these light convert a much higher percentage of the energy into light rather than into heat.
An incandescent light work by passing current through a piece of wire which glows as the electrons pass through. These lights tend to give off a large amount of heat compared to the level of light produced.