What is HDTV?

High-definition television is a high-resolution digital wide-screen TV format. A high-definition TV signal has twice the color resolution and imparts a picture that is six times sharper than that provided by a traditional analog TV set. HDTV likewise provides enhanced audio, such as Dolby Digital.

An image displayed on a TV screen is comprised of small, adjacent rectangles known as "pixels." TV resolution refers to the number of horizontal lines (comprised of pixels) that are displayed on the TV screen. Current High-definition TVs have 1080 horizontal lines - more than twice as many as an analog TV set. High-definition television also differs from standard analog television in pixel size. The pixels in high-definition TV screens are square, smaller and spaced more closely together than in an analog TV set. Finally, high-definition TVs typically employ a 16:9 aspect ratio, or width to height ratio, (i.e., wide screen format; picture 2), rather than the 4:3 aspect ratio (picture 1) utilized by traditional analog TV sets. However, there are some HDTV's that only have a 4:3 screen. Even though high-definition television comes in wide screen format, not all wide screen broadcast is high-definition. DVD's, for example, can sometimes display in wide screen but the content is not necessarily high-definition.

Picture 1		Picture 2
4 : 3		16 : 9

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