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What Do These TV Words Mean?

AARP’s guide to new tech terms

Smart TV


Aspect ratio

The proportion of the television’s pixels by their width and height. Almost all high-definition (HD) TVs have an aspect ratio of 16:9, which means that there are 16 pixels in the width for every 9 pixels in the height.


A disc like a DVD, but with a higher video quality. To watch a Blu-ray disc, you need a Blu-ray player, which will also play DVDs. Blu-ray technology is improving, so now Ultra HD Blu-ray players and discs have begun to hit the market.

Blu-Ray Discs

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A product from Google that allows you to wirelessly broadcast your computer's display to your TV. A Chromecast stick (about 2 inches long) connects to a high-definition multimedia interface (HDMI) port on your TV, which allows you to "cast" anything from your computer or mobile device onto your television screen. 


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Contrast ratio

The disparity between the brights and the darks in the TV's display. The higher the number is, the bigger the disparity is and the better the quality in color.


Short for digital video recorder. A DVR allows you to record broadcast programs to watch later. Most new DVRs allow you to record multiple programs at the same time and have settings that allow you to record all new episodes of a show. Most cable boxes, which you plug into your TV to receive cable channels, come equipped with DVR capabilities, though you may have to pay more for your cable subscription to use it.


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Frame rate

The number of frames per second (fps) displayed by a video. A higher number correlates with a more seamless video. While the human eye can’t generally see the difference after about 120 fps, a higher number always means a higher quality of video.


A type of input that connects set-top boxes, DVD and Blu-ray players, and other devices to your TV through a cable that connects to a port on the TV. HDMI allows for a better picture than auxiliary cables (aka AUX, the traditional cables with red, white and yellow colors that plug into your TV) provide and are used more universally among devices. All HDMI cables are the same, so be wary of ones that are overpriced. You shouldn't spend more than $8 on a cable.

HDMI Cable

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Stands for organic light-emitting diode. When you see terms like LCD (liquid crystal display), LED (light-emitting diode), OLED or plasma, they refer to how light is displayed on the TV. OLED is currently the highest quality technology available on the consumer market, and TVs that include it will almost always be thinner because it requires fewer components built into the hardware to display light.


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On demand

Also called VOD or SVOD (for video or streaming video). On demand (OD) basically means you can watch programs whenever you want. The on-demand service is included in most cable subscriptions to allow you to watch movies, TV shows and special features at your convenience rather than when they air live on a particular channel.

On Demand


Many new episodes of TV shows on broadcast and cable channels are available on demand the day after they air. Some channels, such as HBO, allow you to purchase an on-demand subscription separate from a cable subscription that allows you to watch all of the available content anytime from the moment they air.

Over the top

The term for delivering film and TV content via the internet.


The picture quality of the TV, measured by the total number of pixels (p) in the aspect ratio. While a 720p resolution is considered high definition, the highest class of most commercially available TVs is 4K, which has a resolution of 4096p x 2160p. Resolution technology gets better by the year — nowadays, 1080p TVs are nearly obsolete, with a new influx of 4K screens hitting the market.

Response time

The time it takes for the signal coming into the TV to appear on the screen. Modern TVs have exceptionally quick response times, with 120-hertz (Hz) TVs usually delivering in under 8 milliseconds.

Set-top box

A device that connects to your TV and allows you to watch any content coming from a digital connection. A cable box is a type of set-top box that enables you to watch cable channels and use your DVR if you have a cable subscription. Roku and Apple TV are two other kinds of set-top boxes that allow you to watch content through an internet connection.

Apple TV Box and Remote

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Smart TV

A TV with internet connectivity built in. While some TVs require a device for you to connect to various streaming apps (such as Netflix, Hulu or Amazon Video), smart TVs make a device such as a set-top box, Roku, Xbox or Amazon Fire Stick unnecessary. According to a study by Nielsen published in March 2017, while 42 percent of homes use video game consoles such as Xbox One or PlayStation 4 to stream content, smart TV usage increased from 22 percent to 29 percent over the last year and should continue to rise as more smart TVs hit the market.


Playing media content over an internet connection rather than through a physical medium, such as a DVD, or a downloaded copy. When you watch a movie on Netflix, you don't own the copy of the movie, as you would physically own a DVD. Instead, Netflix licenses the rights to the movie for its customers to watch by using the service, which you pay for through a subscription and connect to via the internet.



Devices such as Roku and Apple TV are devices that enable you to stream content through your TV. Gaming systems, such as Xbox One or PlayStation 4, also come equipped with the ability to download streaming services such as Netflix.

Vertical frequency

The number of times per second the display of the TV refreshes. The higher the number is, the smoother the picture will be, with less motion blur. The highest you'll find in consumer TVs is 120Hz.