LED(Light Emitting Diode) : LED is a semiconductor light source. LEDs are used as indicator lamps in many devices, and are increasingly used for lighting
LCD(Liquid Crystal Display): LCD televisions are thinner and lighter than CRTs of similar display size, and are available in much larger sizes as well
Difference between LED and LCD
1. LED tv uses light emitting diodes as its source of light for the television. An LED tv uses these diodes to create a much more vibrant and colorful image. The blacks are truly black (not dark gray) and the colors are more realistic vs an LCD tv. LED tvs can achieve a contrast ratio of up to 500,000:1. They also in general have a higher refresh rate which will help when watching shows with motion such as sports or movies.
2. LCD televisions use mercury in the manufacturing process versus the LED tv which does not. LED hdtv will also use about 40% less power than the same size LCD tv. LCD or plasma television cost between $10-15 per month to operate.
3. LED televisions are about one third the thickness of the same size LCD tv.