Light emitting Diode, or LED, is a semiconductor source of light which emits a particular light colour while passing current through it. Colour of light depends on semiconductor doping. LED is a specified type of diode. It allows current in forward direction but blocks in reverse direction.

LED is most visible type Diode and can be seen in almost every electronics devices, like TV, & segment, or any type of display devices.

LED is designed to emit light and it is made from a very thin layer of doped semiconder material and colour of light depends on the semiconductor. So, when it is biased, emits a wavelength of the particular spectrum.