LED is a light-producing semiconductor which discharges light when electric current moves through it. The electrons present in the semiconductor get attached with electron holes and release photons (energy). The shade of the light is dictated by

Unlike the CRT (Cathode Ray Tube), the LCDs (Liquid Crystal Display) are not able to produce light of its own. Thus it uses a backlight that provides illumination to it. Backlight provides illumination to the LCD from the back and side of the dis