LED TV is a type of LCD television that uses light-emitting diodes (LEDs) to backlight the display
instead of the cold cathode fluorescent lights used in standard LCD televisions.

Blu-ray is a media format designed to replace the DVD format.
Blu-ray uses a different type of laser to read the discs, allowing more data to be stored on a single disc.

As Blu-ray can store more data, it can provide a much better picture (HD)
than the DVD format as well as better audio.

Home theater is a setup of audio and video equipment in your home
that tries to duplicate the movie theater experience.

The Digital Versatile Disc (DVD) is an optical information storage technology with multiple applications.
Lasers read pitted digital patterns stamped on DVDs.