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Demystifying HDTV Terminology

We translate the technobabble and help you select your next set.

As if buying a new television wasn't stressful enough — as you wrestle with the cost, how to install it and what to do with your existing TV — you'll also need to make some sense of the new buzzwords out there.

Jargon phrases, acronyms and numbers go in one ear and out the other, be it "1080p," "HDMI," "ATSC," "240Hz," "widgets" or "LED." Huh? You probably — and justifiably — feel like you need a degree in electrical engineering just to understand it all.

Although the jargon is confusing, the technologies behind it are designed to enhance your television experience. Each of them handles this task in a different way, however, such as providing a picture with more detail and depth (1080p and LED, respectively), delivering smoother motion (120Hz or 240Hz) or supporting Internet connectivity (widgets).

The manufacturer and screen size you choose depend on your personal preferences and budget, but many of these techie terms do offer some worthy benefits to keep in mind when you're shopping for a high-definition television (HDTV).

Consider the following a handy geek-to-English dictionary.

16:9 and 4:3

These numbers, known as the aspect ratio, refer to a TV's dimensions and shape; they express the ratio of the width of the screen to its height. HDTVs are wide-screen televisions, with a 16:9 aspect ratio that is more akin to a movie theater's rectangular screen than the almost-square 4:3 televisions of yesterday. When you go to buy a TV, though, you will still — as with older sets — be choosing a size based on the diagonal dimension of the screen, such as 32" or 54".

1080p and 720p

A "pixel" is a little dot of information, and a high-definition television is capable of displaying up to 1,920 pixels by 1,080 pixels on its screen. By comparison, older standard-definition televisions had about 720 by 480 pixels. This translates to a lot more detail and clarity. You will see HDTVs today referred to as "1080p" or "Full HD" televisions, meaning all the lines of resolution on the screen are shown "progressively," displayed in sequential order in a single pass (1, 2, 3, etc.), as opposed to the older 1080i ("interlaced") method of alternating between even and odd lines to make up the image (1, 3, 5, etc.). This results in a smoother, richer picture when the TV is connected to a 1080p source, such as a Blu-ray Disc player or high-definition video game console, such as an Xbox 360. Going from DVD to Blu-ray Disc is like putting on a pair of prescription glasses for the first time: Everything is clearer, and minute details are easily seen.

On the sales floor of your local electronics retailer, you'll notice the availability of 720p HDTVs, which display 1,280 pixels by 720 pixels. Although these sets are capable of displaying a 1080i image (the minimum for "HD" designation), they do not provide the same amount of detail as 1080p screens. 720p screens allow you to view an ultracrisp image on screens 37" or smaller. Any size bigger than this — at normal viewing distances — and you'll notice the lack of detail compared to the 1080p.

LCD, LED and Plasma

Plasma televisions consist of a glass panel of plasma cells that, when electrified, produce a picture. LCD technology involves the placement of liquid crystals between two panels of glass, which are then electrified to produce an image. Until recently, plasma-based televisions held a discernible advantage over LCD TVs when it came to "contrast ratios" — the difference between the brightest whites and the blackest blacks displayed on the screen — but this gap has been bridged considerably with something called LED backlighting.

In LCD TVs that employ LED technology, "light-emitting diodes" are placed behind the liquid crystals, resulting in better contrast, high brightness and more vivid colors. Plus, LED TVs — whether they're "edge-lit" (the LEDs placed around the edges of the television) or "backlit" (a full array of LEDs behind the entire screen) also are thinner than conventional LCD TVs and far more energy-efficient, too.

On an LCD TV without LED backlighting, the color black tends to look more grayish because there's still a bright light on behind the pixels.

LED TVs cost more than regular LCD TVs, but movie lovers definitely prefer them.

120Hz and 240Hz

Pronounced "120 hertz," 120Hz technology essentially doubles the speed at which frames are displayed, from 60 frames per second to 120 frames per second, resulting in a clearer moving image — especially in fast-action video sequences. This popular LCD TV-based technology helps reduce motion blur. Sony often refers to it as MotionFlow.

Some LCD TVs now offer 240Hz motion technology, which — yep, you guessed it — quadruples the speed of the 60 frames per second video source.

Plasma TV shoppers need not worry about this terminology as plasma TVs handle motion very well.


Many of the top television manufacturers — including Sony, Sharp, Panasonic and Samsung — include Ethernet jacks on the back of their premium televisions for high-speed Internet connectivity, or in some cases, they have integrated Wi-Fi for wireless connections.

TV viewers then use the remote to select "widgets," graphical icons on the screen that play relevant (and customized) content ranging from YouTube videos and Flickr photo galleries to local weather, news, sports updates and stock quotes. Some Internet-connected TVs also let you stream Netflix movies on your television, with tens of thousands of titles available — many of which are in high definition.

ATSC and NTSC Tuners

While most TVs have a built-in NTSC (National Television Standards Committee) tuner — the same video standard used by the television industry in North America (and some Asian countries) for the past half-century or so — newer TVs might also include an integrated ATSC (Advanced Television Systems Committee) tuner.

An ATSC tuner is a handy addition to your TV because it allows you to receive many free over-the-air high-definition broadcasts (depending on where you live).

Some HDTV owners don't subscribe to a television provider's service at all, and instead pick up these HD signals over the airwaves for free.


While these haven't caught on just yet, a number of television manufacturers are delivering a movie theater-like three-dimensional ("stereoscopic") effect for your home theater.

Viewers have to wear special glasses, which may or may not have shipped with the television, for the eye-popping visuals. And of course, you also need 3D content to watch, too, such as a 3D movie on Blu-ray Disc (for example, Cloudy With a Chance of Meatballs or Monsters vs. Aliens 3D) or 3D programming, such as a televised sporting event (ESPN recently launched a 3D channel).

There's a bit of a price premium for these 3DTVs, but they also function as top-of-the-line 2D televisions.

Toshiba and Sony both announced they're developing 3D televisions that don't require glasses, but they'll likely be even more expensive; you'll need to sit in a specific spot to see the 3D picture; and the effect won't be as striking as 3DTVs that work with 3D glasses.

HDMI, USB, Memory Cards

A final consideration when buying a new HDTV is what you can connect to it. Make sure there are ample HDMI (High-Definition Multimedia Interface) ports to connect multiple components, such as a cable/satellite receiver, video game consoles, DVD/Blu-ray player, camera or camcorder, and so on. At least three or four such ports are a must.

A convenient bonus is when the TV also offers a USB port to connect a Flash thumb drive or external hard drive full of music, photos and videos, or an SD or memory-stick card slot that lets you insert a compatible card containing media to enjoy on the big screen.


Are all of these technologies necessary? Not really. Here's a quick a look at what you should look for and what's a convenient bonus.

720p video display 1080p (screens bigger than 37")
120Hz 240hz
LED (if buying LCD) or Plasma 3DTV (3D movies in your living room!)
NTSC tuner ATSC tuner (free, over-the-air HD broadcasts)
3 HDMI inputs More than 3 HDMI inputs
  Widgets (apps)
  USB/Memory card readers