LED stands for light–emitting diodes, which are semiconductor devices that produce visible light when an electrical current passes through them. LED lighting is different from incandescent and compact fluorescent lighting in that it is more durable, longer-lasting and more energy efficient.
When an electrical current passes through the semiconductor material, the tiny light sources in an LED are illuminated. LED light colors are commonly amber, red, green, and blue. LED lights do not come in true white, but different colors are mixed and covered with a phosphor material that converts the color of the light as required. Phosphor is the yellow material that can be seen on some LED products.
Colored LED lighting is used widely in indicator and signal lights, such as the power button on a computer. LED lighting is a directional light source, which means that each device emits light in a certain direction. Incandescent and compact fluorescent bulbs emit light and heat in all directions. This is why LED lighting uses energy more efficiently.
LED lighting also does not radiate heat the way a halogen or incandescent light bulb does, further increasing its efficiency. Energy that is transformed into heat rather than light is wasted energy within a lighting solution.