3D simply refers to a three-dimensional space. Many HDTVs, Blu-rays, and video games now have 3D capabilities, but not all 3D is created equal. You may be familiar with the older anaglyph 3D technology using red and blue glasses. Instead of having images appear to pop out of the screen, modern stereoscopic 3D is about creating the appearance of depth. Most 3D HDTVs require stereoscopic 3D glasses, though autostereoscopic (or glasses-free) 3D TVs have been produced. See Active 3D and Passive 3D for more information about the types of 3D technology found in HDTVs.


Active 3D:

A type of stereoscopic 3D present in many 3D HDTVs, Active 3D uses battery-operated shutter glasses that rapidly shutter open and closed. This allows each eye to get the full 1080p resolution of the source, though the glasses block some light, which could make the image look dimmer.


Analog TV:

Encodes picture and sound information and transmits an analog signal. All systems preceding digital are analog. As of February 17, 2009, analog signals are no longer broadcast.


Aspect ratio:

The ratio of width to height for an image or screen. HDTVs use the widescreen 16:9 format, as compared to the square-ish 4:3 aspect ratio of standard definition televisions. This means you'll have a wider picture and see more content on the left and right sides of the screen. Standard definition content may still appear in 4:3 on a widescreen HDTV.


ATSC (Advanced Television Standards Committee):

This was formed to establish technical standards for the U.S. digital television system. A TV tuner that can receive local over-the-air digital broadcasts is often called an ATSC tuner.


Audio/video inputs:

The ports on a television used to connect external devices, like DVRs, Blu-ray or DVD players, video game consoles, and surround-sound systems. Examples include HDMI, component, and composite inputs; see definitions for more information.



Literally, light that comes from the back of a TV. In modern HDTVs, this typically refers to LED backlighting, which allows a thinner panel, lower power consumption, better heat dissipation, a brighter display, and better contrast levels.



A form of wireless communication allowing devices to communicate with each other. For example, a Bluetooth keyboard could be connected to your Bluetooth-enabled HDTV without the need for cables. Some 3D HDTVs even use Bluetooth 3D glasses, which results in a better line-of-sight and reduces interference from lights in the room.


Built-in tuner:

Refers to a tuner that's integrated into the TV, eliminating the need for a set-top box.



This refers to a TV screen being permanently damaged by a static image being displayed for too long a period of time. Though not as persistent a problem as it was on older TVs and early plasma displays, burn-in can occasionally plague newer models. Check with your manual for more information and best practices.


Closed Captioning:

A text stream that appears on screen to provide narrative description of dialogue, action, and sounds of the picture.


Cloud TV:

A Smart HDTV with specific streaming features, which vary from manufacturer to manufacturer. Examples of Cloud TV streaming features include local, national, and international TV channels, news, weather, and personal calendars and messaging.


Comb filter:

Comb filters are used on HDTVs to clean up the image and reduce fuzziness and distortion, particularly when displaying a lower resolution composite signal. A digital comb filter separates the video signal to create more vibrant colors.


Component video:

Typically split into three channels (that would be those red, blue, and green ports), component video displays higher resolutions than composite, typically 720p or 1080i. This makes it better than composite but not quite as good as HDMI in terms of video quality. See resolution for more info.


Composite video:

An analog video transmission that carries standard definition video. You may know this as the yellow cable (often accompanied by red and white audio cables) that connects standard-definition devices to the matching color-coded ports on your television.


Contrast ratio:

Measures the difference between the brightest whites and the darkest blacks that a TV can display. The higher the contrast ratio, the better a TV will be at showing subtle color details, and the better it will look in rooms with more ambient lighting.


Deep Color:

A color resolution standard associated with high-definition TVs and video gear that include HDMI 1.3 and up connections. Deep Color supports 10-bit, 12-bit, and 16-bit color bit depths, up from the 8-bit color supported by earlier versions of HDMI. A higher color bit depth enables finer gradations between different shades of the same color, for smoother gradients and reduced color banding.



The process of converting an interlaced scan video signal (where each frame is split into two sequential fields) to a progressive-scan signal (where each frame remains whole). Deinterlacers are found in HDTVs and progressive-scan DVD players. This makes HDTVs capable of displaying video with interlaced signals, such as a broadcast standard-definition television signal.


DLNA (Digital Living Network Alliance)-certified:

DLNA-certified electronics are designed to work with each other using your home network. For example, your DLNA Smart HDTV would be able to easily stream media to your DLNA-certified computer. However, not all DLNA certifications are created equal; some only stream photos and music, while others are capable of streaming video.


Digital audio output:

A port on your HDTV used to connect your surround-sound system. The two most common types of digital audio output are optical, which uses a light-based cable, and coaxial, which requires an RCA cable.


Dolby Digital:

A multichannel digital audio format that is the official audio standard for HDTV. Dolby Digital is normally associated with 5.1 surround sound. Though this channel configuration is the most common, it is only one of several possible variations. A Dolby Digital soundtrack can mean anything from 1 to 5.1 channels, while Dolby Digital Plus can produce up to 7.1 surround sound (though it requires an HDMI cable to do so).


dts Audio:

Refers to digital surround sound technology made by DTS, Inc. There are several variants in use today, such as the standard 5.1-channel dts Surround codec and dts-HD High Resolution Audio, which allows for up to 7.1 audio channels. See surround sound for more info.



The process in which a high-definition signal is converted to be displayed on a television with a lower resolution, such as a 1080i HDTV broadcast displayed on a 720p TV. Downconversion reduces image detail, but downconverted pictures can still look very sharp.


DTV (Digital Television):

A general term for the ATSC digital broadcast TV standard, which replaced the NTSC analog broadcast system. DTV comes in two basic types: widescreen, high-quality HDTV (High-Definition Television) with Dolby Digital audio and medium-quality SDTV (Standard-Definition TV).


DVI (Digital Visual Interface):

A digital interface with a multi-pin connection used to connect a video source to a display device. DVI has largely been replaced by HDMI and DisplayPort interfaces.



Refers to an LCD panel that's LED-illuminated from its edges rather than from behind. This results in greater illumination across the background of the panel and the image appears smoother and more even than a traditional panel. It also makes the panel thinner, allowing it to fit in tight spaces such as small TV cabinets or on walls.


Flat-panel TV:

Any ultra-thin, relatively lightweight TV. Current flat-panel TVs use either plasma or LCD screen technology.



In moving picture media, whether film or video, a frame is a complete, individual picture. The rate at which frames are displayed is called, appropriately enough, the frame rate.


Full HD:

This refers to displays with a resolution of 1920x1080, also written as 1080p. The "p" stands for progressive scan, which means that each video frame is transmitted as a whole in a single sweep. See "resolution" for more information.


Gaming mode:

Some HDTVs have game or gaming modes for playing video games. Gaming modes are designed to reduce input lag, meaning cutting down on the time (usually in milliseconds) it takes for a gamer's input on a controller to be registered on the screen. Input lag can also cause audio to not match up with on-screen action, like when a character's lips don't match up with the dialogue. While gaming modes cut down on input lag, they do so at the expense of image quality.


Google TV:

A Smart HDTV that utilizes many of Google's existing products. Google TVs use an Android™ operating system, Google Chrome browser, and Google Play app store. By creating an interactive television overlay, Google TVs allow users to do things like browse the Web while watching television.


HDCP (High-Bandwidth Digital Content Protection):

HDCP encryption is used with high-resolution signals over DVI and HDMI connections to prevent unauthorized duplication of copyrighted material.


HDMI (High-Definition Multimedia Interface):

The HDMI interface transfers uncompressed digital video with HDCP and multichannel audio. HDMI inputs are used to connect high-definition devices like HD cable boxes, Blu-ray players, and video game consoles through the use of HDMI cables. Many current HDTVs use the HDMI 1.4 interface (released in 2009), which supports resolutions up to 3840x2160. HDMI 2.0, released in September 2013, supports 4K resolution at 60 frames per second, making it preferable for Ultra HDTVs (see Ultra HD for more information).



An HDMI feature that allows you to command and control up to 15 CEC-enabled devices connected through HDMI with a single remote control. For example, using HDMI-CEC, you could use one remote for your HDTV, DVD player, and cable box. HDMI-CEC is often referred to by manufacturer-specific terms: Anynet+ (Samsung); AQUOS Link (Sharp); BRAVIA Link and BRAVIA Sync (Sony); SimpLink (LG); VIERA Link (Panasonic); and so forth.


HDTV (High-Definition Television):

As you've probably realized by now, HDTV specifically refers to a television set capable of displaying high definition. Though some models may top out at 720p, 1080p (Full HD) is generally the standard for HDTVs, and 4K resolution Ultra HDTVs are also rising in prominence.


Hertz (Hz):

A measure of frequency, where one Hertz equals one cycle per second. In video, Hertz is used to describe a frame rate in frames per second. For example, you'll often see 24-frames-per-second video listed as "24Hz."


Intel WiDi:

Short for "wireless display," WiDi technology allows you to display content from a similarly enabled computer to your HDTV wirelessly.


LCD (Liquid Crystal Display):

A prevalent model of HDTVs, LCDs are flat panel displays through which light can pass or be blocked. The LCD doesn't produce its own light; this is done by additional lighting (see Backlit and Edge-lit for more info). LCD HDTVs are available in a variety of sizes and have wide viewing angles, making them ideal for almost any size room.


LED (Light Emitting Diode):

A semiconductor device that produces light from electricity. LEDs are often used to backlight LCD displays, which results in a clearer picture.


Letterboxed video:

A method for displaying the entire picture as seen in a movie theater on a TV screen. The resulting image width is much greater than its height. On an old-fashioned TV screen with 4: 3 aspect ratios, letterboxed videos appear with horizontal black bars above and below the image. You will often see the black bars when watching older movies on a widescreen TV.


Local dimming:

On LED-backlit LCD HDTVs, local dimming refers to sections of the LED array becoming dimmed or turning off entirely to help produce deeper blacks. This helps create a better contrast, making the picture look better overall, but can sometimes create a slight halo effect around bright objects on the screen.


Megahertz (MHz):

Equal to one million Hertz. Video signal bandwidth is typically expressed in megahertz.


MHL (Mobile High-definition Link):

An MHL-compatible HDMI port allows you to easily view media from your MHL-compatible smartphone or tablet on your HDTV through the use of an MHL adapter cable. MHL ports support 7.1-channel audio and 1080p video.


MPEG (Moving Picture Experts Group):

The organization charged with developing video and audio encoding standards. On the video front, consumers are most likely to encounter the MPEG-2 and MPEG-4 compression formats, or "codecs." These formats are capable of producing very high-quality video by employing an adaptive, variable bitrate process that can allocate more bits for complex scenes involving a lot of motion, while reducing the bits in static scenes.



Used for over-the-air digital television broadcasts, standard DVDs, some Blu-ray discs and HD DVD discs, and small-dish satellite TV.



This newer, more efficient format has become the standard, and absorbs many of the features of its predecessor, MPEG-2.


NFC (Near Field Communication):

An electromagnetic wireless technology that enables communication between two devices. An HDTV with NFC technology can instantly connect with an NFC-enabled mobile device simply by tapping the device against the TV. NFC has a much shorter range than Bluetooth, but may be quicker and more convenient in some cases.


Noise reduction:

In this case, "noise" refers not to sound but to TV noise, which could be film grain, pixilation, compression artifacts, or generally any unwanted addition to the image. Typically helpful when watching standard definition broadcasts or media on an HDTV, noise reduction may result in a better picture while sacrificing some detail and possibly creating motion blur. It likely won't be necessary when viewing HD channels or media.


NTSC (National Television System Committee):

The North American 525-line analog broadcast TV standard, which was established over 50 years ago. The ATSC digital broadcast standard replaced NTSC on June 12, 2009.


OLED (Organic Light Emitting Diode):

A display technology used to create flat panel TVs. Each pixel in an OLED HDTV illuminates itself and becomes pitch black when not active; as a result, OLEDs have bright displays, completely black blacks, wide viewing angles, and contrasts not capable on LCD displays. Though capable of great pictures, OLEDs sometimes have slightly curved displays that usually can't be wall-mounted, so they're not ideal for every home.



The extra space around the four edges of a video image that may not be seen reliably by the viewer. Overscan exists because television sets in the 1930s through 1970s were highly variable in how the video image was framed within the old-school CRT televisions. For 16:9 aspect ratios, around 3.5% Overscan is considered acceptable for action, with 5-10% Overscan ensuring that text won't be cut off. Some HDTVs now have 1:1 pixel matching and/or 0% Overscan features, which means your TV is capable of displaying the image pixel for pixel, without scaling or processing the video in any way.


Passive 3D:

Passive 3D HDTVs use polarized glasses like those found at most movie theaters. The TV uses a special filter that polarizes each line of pixels, meaning that the odd lines on the screen are only visible to the left eye, and the even lines are only visible to the right. The screen will look normal without glasses. Polarized glasses are typically less expensive than the shutter glasses used for Active 3D HDTVs, but they lower the resolution of the image, and you may be able to see the interlace lines on some displays.


PC Input:

Often listed as a VGA or DVI port, this input allows you to connect your computer to your HDTV, allowing you to display computer images on the television screen.


Pillar-boxed video:

The pillar-box effect refers to the vertical black bars placed on the sides of a 4:3 image when viewed on a 16:9 display. See aspect ratio for more information.



Short for "picture element," a pixel is the smallest bit of data in a video image. As pixel size gets smaller, more pixels can fit in the same screen area, increasing picture resolution.



Like computers, tablets, and smartphones, internet-enabled televisions also have processors to improve performance. A processor built into an HDTV is designed to make it more responsive, allow multi-tasking support, and possibly even improve the picture quality.



Along with LCD and LED LCD, plasma is a popular type of HDTV display. While early plasma models were often subject to burn-in, more recent models have technology to reduce its effects. Plasmas can be advantageous because the displays produce deeper blacks for superior contrast ratio, have wider viewing angles than standard LCD displays, and generally have high refresh rates and a faster response time. However, plasma HDTVs also use more energy than LCDs, burn-in may occasionally still be an issue, and plasmas are often thicker than LCD displays of the same display size.


Progressive Scan:

Some digital television broadcast formats and most DVD players use a type of video signal known as progressive scan. Instead of splitting each video frame into two sequential fields like analog-interlaced NTSC video, progressive scan video displays the entire frame in a single sweep. As a result, motion appears smoother and more realistic.


QAM (Quadrature Amplitude Modulation) tuner:

A QAM tuner allows cable subscribers to tune in unscrambled cable channels without a separate set top box, including high-definition channels, if the cable service provider offers them.


Refresh rate:

The number of times per second in which the display draws the data it is being given. In theory, the faster the refresh rate, the smoother the picture. This is typically helpful when it comes to action scenes, sports, or anything involving fast motion, as it helps reduce motion blur. There is some debate about whether super-high refresh rates (higher than 120Hz) result in an artificial-looking picture, but that's ultimately a matter of preference. With modern LCD displays cutting down on motion blur, very little should be noticeable with a refresh rate of 60Hz.


Region Code:

A DVD coding system enforced by the movie industry that is intended to preserve movie distribution rights and agreements. Movies are released in theaters in different parts of the world at different times. DVD players and DVDs are labeled for operation within a specific geographical region in the world. For example, the U.S. is in region 1. All DVD players sold in the U.S. are made to region 1 specifications. Region 1 players can only play region 1 discs.


Remote app:

An application that allows you to use your smartphone or tablet (typically limited to iOS and Android) as a remote control for your HDTV.


Response Time:

The amount of time it takes for a single pixel in a video display to switch from active to non-active; it is measured in milliseconds (ms). If a display's response time is too slow, faint motion trails may be visible following fast-moving on-screen objects such as in sports images. Current HDTVs usually have response times that are just a few milliseconds; generally, the faster the better.


SDTV (Standard-Definition Television):

SDTV refers to the non-high-definition formats in the ATSC digital television standard. SDTV pictures can have either 4:3 or 16:9 aspect ratios. Picture and sound is clearer than analog NTSC video, with picture resolution of 480i or 480p. These digital signals require less bandwidth than analog signals, allowing TV stations to simultaneously broadcast multiple channels of programming in place of a single analog channel also known as multicasting.


Set-top Box (STB):

Also called converter boxes, these receivers convert broadcasts (either over-the-air broadcast HDTV, analog cable, digital cable, satellite, or Internet-based IPTV) for display on a television.



Skype is a free application that allows you to make video calls to anyone with a Skype account and an internet connection. (Some advanced options may require paid subscriptions, but person-to-person calls are free.) Some Smart HDTVs have Skype pre-installed, meaning all you need to do is add a camera to enjoy high-quality video calls on the big screen. Not just any webcam will work; a TV-specific camera with a microphone that picks up sounds from further distances is needed. Some higher-end Smart HDTV models come with built-in cameras.


Smart TV:

A Smart HDTV is one that has built-in Internet capabilities, typically providing both Wi-Fi and ethernet options. Smart TV features vary slightly from brand to brand, but generally include Web browsing, social media, apps, and streaming services, which can be accessed right on the TV screen.



Refers to the process of watching or listening to multimedia broadcast over the internet. For example, when you are watching a movie on a subscription service like Netflix or listening to music on Pandora, you are streaming that media.


Surround sound:

A technique used to enhance audio by surrounding the listener with additional audio channels (speakers). The most commonly used surround-sound layout is 5.1 surround sound, which utilizes front right and left channels, a center channel, two surround channels, and a subwoofer. Some home theater set-ups use 7.1 surround, which expands on the 5.1 set-up by splitting the front and surround channels into four distinct channels: left and right surround and two rear surround channels. While external speakers are needed for true surround sound, some HDTVs come with virtual or simulated surround sound, which uses two channels. It's not quite the same, but can be useful if you don't want to run wires through your living room, have a small space, or simply don't want to purchase extra equipment.


Ultra HD:

Ultra HD refers to displays with a resolution of at least 3840x2160 (sometimes referred to as 4K or 4K2K resolution) and aspects ratios of at least 16:9. This presents a picture that's several times as clear as Full HD resolution. Though 4K technology first made its mark in movie theaters, Ultra HDTVs rose to prominence in 2013. As "next generation" TV technology, there aren't as many Ultra HD entertainment options available as there are in Full HD, though 4K is becoming increasingly popular. A few TV shows are now shot in 4K, but it's not yet the standard; however, 4K media players may allow you to watch films in Ultra HD resolution. Additionally, the Xbox One and PlayStation 4 consoles have some 4K compatibility.



Also known as upscaling, this term is used to describe the conversion of a lower resolution to a higher resolution. For example, some high-definition Blu-ray players have a feature that upscales regular DVDs. This process increases the number of pixels and/or frame rate and/or scanning format used to represent an image by interpolating existing pixels to create new ones at closer spacing. While the upconverted image won't be displayed in true Full HD, it will look better than it did at its original resolution.


USB (Universal Serial Bus) port:

A high-speed serial port technology that allows easy attachment and detachment of compatible devices. Though it varies from model to model, HDTVs with USB ports typically allow photo or music files from a flash drive or compatible USB device to be displayed or heard on the television.



A type of parental control, V-chip technology blocks the display of certain television programs based on their rating. Broadcasters are required to encode an electronic signal in TV programs indicating the level of violence, language, and sexual content. Parents can program the TV with a rating so that when the V-chip reads a show's signal, it will prevent it from displaying if it is above the rating.


Viewing Angle:

Measures a video display's maximum usable viewing range from the center of the screen, with 180 being the theoretical maximum.



Many HDTVs can now be mounted directly to the wall or a vertical stand, rather than being displayed on top of a flat surface. VESA is the standard for mounting flat-screen devices, and each television's pattern size (such as 200x200, 400x400) correlates to its weight and size.


Web browser:

A software application used to access the World Wide Web. Commonly used browsers include Google Chrome, Mozilla Firefox, Internet Explorer, Opera, and Safari®.



When used to describe an HDTV, widescreen generally refers to an aspect ratio of 16:9, which is the optimum ratio for viewing high-definition content.