LEDs are monochromatic devices. The color is determined by the band gap of the semiconductor used to make them red, green, yellow and blue. Light Emitting Diodes (LED) have recently become available in white and bright, so bright that they seriously compete with incandescent lamps in lighting applications. Bright white Light emitting diodes, commonly called bright white LED, is widely used in the electronics world. They do dozens of different jobs and are found in all kinds of devices. It is solid semiconductor which is able to transferred electrical energy into visible lighting. The core of the LED is semiconductor crystals, which consist by a P semiconductor and an N semiconductor, thus form a p-n junction. This semiconductor could lighting up when it power on. In contrast to most light sources, bright white LED has many benefits which include high reliability, long lifespan, high shock and vibration resistant and high luminous flux output. The solid package of this LED can be designed to focus its light instead of an external reflector used in incandescent and fluorescent sources. Moreover, white LED doesn't contain mercury, unlike fluorescent lamps. It is also has small size and can be used combined with other electrical component such as sensor, dimmers and lighting control.