LED stands for light-emitting diode. LEDs are small light sources that become illuminated by the movement of electrons through a semiconductor material. LEDs can be integrated into all sorts of products to provide white and colored light, such as flashlights, light bulbs, and integrated light fixtures.

What makes an LED

LED lighting starts with a tiny chip (most commonly about one square millimeter) comprised of layers of semi-conducting material. LED packages may contain just one chip or multiple chips, mounted on heat-conducting material called a heat sink and usually enclosed in a lens. The resulting device, typically around 7 to 9 mm on a side, can be used separately or in arrays. LED devices are mounted on a circuit board, which can be programmed to include lighting controls such as dimming, light sensing and pre-set timing. The circuit board is mounted on another heat sink to manage the heat from all the LEDs in the array. The system is then encased in a lighting fixture, architectural structure, or even a “light bulb” package.

Low-Powered LEDs

LEDs used to draw attention to something, such as an exit sign,
a green power button on a computer, or a red blinking
light on a video camera.

High-Powered LEDs

LEDs used to illuminate an area. ENERGY STAR qualified LED lighting uses

multiple illuminator LEDs inside a fixture to produce white light.

 

What is Solid-State Lighting?

Many tiny LEDs are used in each fixture. LEDs are part of a family of lighting technologies called Solid-State lighting. This family also includes OLEDs (Organic Light Emitting Diodes). OLEDs (pronounced OH-leds) consist of sheets of carbon-based compounds that glow when a current is applied through transparent electrodes. While not yet market ready, OLEDs will function like a thin film on a wall or ceiling that illuminates a room. Like LEDs, OLED technology is advancing rapidly.

Solid-State lighting (SSL), most commonly seen in the form of Light Emitting Diodes (LEDs), has the potential to revolutionize the efficiency, appearance, and quality of lighting as we know it.

How are LED lighting products different from other lighting, like fluorescent or incandescent?

LEDs emit light in a specific direction, whereas an incandescent or fluorescent bulb emits light — and heat — in all directions. For direct lighting applications LED lighting uses both light and energy more efficiently.

For example, an incandescent or compact fluorescent (CFL) bulb inside of a recessed can will waste about half of the light that it produces, while a recessed down light with LEDs only produces light where it’s needed — in the room below.

Incandescent bulbs create light by passing electricity through a metal filament until it becomes so hot that it glows. Incandescent bulbs release 90% of their energy as heat.
In a CFL, an electric current is driven through a tube containing gases. This reaction produces ultraviolet light that gets transformed into visible light by the fluorescent coating (called phosphor) on the inside of the tube.
LED lighting products use light emitting diodes to produce light very efficiently. The movement of electrons through a semiconductor material illuminates the tiny light sources we call LEDs. A small amount of heat is released backwards, into a heat sink, in a well-designed product; LEDs are basically cool to the touch.
Incandescent bulbscrqeate light by passing electricity through a metal filament until it becomes so hot that it glows. Incandescent bulbs release 90% of their energy as heat.
In a CFL, an electric current is driven through a tube containing gases. This reaction produces ultraviolet light that gets transformed into visible light by the fluorescent coating (called phosphor) on the inside of the tube.
LED lighting products use light emitting diodes to produce light very efficiently. The movement of electrons through a semiconductor material illuminates the tiny light sources we call LEDs. A small amount of heat is released backwards, into a heat sink, in a well-designed product; LEDs are basically cool to the touch.

Source: EnergyStar

Please feel free to use this conversion chart from Incandescent/Halogen bulbs and Florescent  bulb to the compatible LED.