Light Emitting Diodes - popularly known as LEDs - are devices which are very commonly used in our day to day life, whether we realize it or not. They have been put to use in a wide variety of appliances and does varied functions. From the tiny lights which blink in equipments to indicate the status, numbers on the digital clocks and messages on the sign boards to television screens which get lighted up by LED's, it has a wide range of requirement and usability. Infrared LEDs are used in remote control devices, cameras and similar gadgets.

LED lights works on the principle of the semiconductor diode. When electricity is passed through it, light of a particular frequency is emitted. Light is made up of a collection of photons propagated as electromagnetic waves. It can be produced by incandescence as well as electroluminescence. The difference between the normal bulb and LED bulb is in how light is produced. A normal bulb, which we call the incandescent bulb, produces light by the heating up of a filament. When the filament is heated up, photons are emitted. In the case of an LED bulb, cold light is produced by electroluminescence, where photon emission happens when the semiconductor material is electronically excited. Hence they do not require a warm up time to get lighted up, it does not have a filament which will burn out eventually and the loss of energy as heat is absolutely avoided.

The emission of light from LED lights is usually in one direction, which reduces the amount of light lost due to scattering. This property when combined with lower levels of power consumption as well as energy loss due to heat, makes it highly efficient for lighting. LED lamps are highly resistant and tolerant to vibrations and heavy shocks. They exhibit longevity and constant use will not result in abrupt failure but only in gradual loss of brightness. This makes them fit for applications like traffic lights where an abrupt failure might prove to be disastrous. Moreover, their small size enables them to be easily accommodated in any kind of electric circuit and is usually used in numbers so that the failure of one LED light will not account to a total failure of the system. They can be easily dimmed and brightened by reducing the power or by switching it on and off in fast cycles; unlike in incandescent lights, power efficiency is still maintained when an LED light is dimmed.

There are different types of LEDs – those which emits visible light, infrared rays, ultraviolet rays etc. Another variant is the organic LED which uses organic compounds for its production. They vary in the kind of light produced, color and visibility. Each type can be used for different types of applications. There are wide ranges of advantages this energy efficient lighting over the conventional methods of lighting up, ranging from usage simplicity to high returns on investments and cost benefits to high environmental impacts. It is needless to say that LED's are going to be the future answer for household & industrial lighting as well as for a diverse range of use in varied product ranges.