(Light Emitting Diodes) work on a completely different concept. Traditionally LEDs are created from two semiconductors. By running current in one direction across the semiconductor the LED emits light of a particular frequency (hence a particular color) depending on the physical characteristics of the semiconductor used. The semiconductor is covered with a piece of plastic that focuses the light and increases the brightness. These semiconductors are very durable, there is no filament, they don't require much power, they're brighter and they last a long time. By densely packing red, blue and green LEDs next to each other on a substrate one can create a display. The disadvantage of LEDs is that they are much larger – therefore the resolution is not nearly as good as LCD displays. That's why most LED displays are large, outdoor displays, not smaller devices, like monitors.

Light emitting diode. Small indicator lights on electronics and networking devices that provide indication of status and other information about the device.

Abbreviation of light emitting diode, an electronic device that lights up when electricity is passed through it. LEDs are usually red. They are good for displaying images because they can be relatively small, and they do not burn out. However, they require more power than LCDs.