What Is HDTV? > Glossary

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1080i: This is 1080 lines of interlaced video (540 lines per field). Two fields, interlaced provides a full picture (frame). Usually refers to 1920x1080i resolution in 1.78 (16:9) aspect ratio.
1080p: 1080 lines of progressive video (1080 lines per frame). Usually refers to 1920x1080 resolution in 1.78 aspect ratio. This image is not interlaced like 1080i.
16:9: Aspect ratio most commonly known as wide screen and is wider than the standard 4:3 aspect ratio. Also referred to as 1.78 aspect ratio (16/9). 16:9 supporters state that the wider picture corresponds much better to the human visual field than the almost square 4:3.
2-3 pulldown: An uncommon variation of 3-2 pull down, where the first film frame is repeated for 2 fields instead of three. Most people mean 2-3 pull down when they say 3-2 pull down. Videographers find 2-3 pull down the best way to process film to video, but still call it 3-2 pull down.
3-2 pulldown: The process of converting 24-frame-per-second film to video by repeating one film frame as three fields, then the next film frame as two fields.
480i: 480 lines of interlaced video (240 lines per field). Usually refers to 720x480 (or 704x480) resolution.
480p: 480 lines of progressive video (480 lines per frame). 480p60 refers to 60 frames per second; 480p30 refers to 30 frames per second; and 480p24 refers to 24 frames per second (film source). Usually refers to 720x480 (or 704x480) resolution.
5C: See DTCP, the correct name for 5C (a term which refers to the 5 companies that created the encryption technology).
525/60: The analog TV system (NTSC) used for years in the US, which is a scanning system of 525 scanning lines (presented as 240 scan lines (a field), interlaced, displaying 480 total lines of visible picture (a frame)), at 60 hertz. This 60 hertz scanning rate results in a full frame every 1/30 of second. The 45 scanning lines not displayed is known as the VBI (vertical blanking interval), which contains certain signals which control the TV's scanning system and other functions.
5.1 Audio: In contrast to the Stereo sound system and conventional Surround Systems, this sound system offers five separate full band audio signals: Left, middle, right, rear left, and rear right. An additional subwoofer (LFE) channel is also provided.
625/50: The analog TV system (PAL/SECAM) used in Europe and other countries, which is a scanning system of 625 scanning lines (presented as 265 scan lines (a field), interlaced, displaying 580 total lines of visible picture (a frame)), at 50 hertz. This 50 hertz scanning rate results in a full frame every 1/25 of second. The 45 scanning lines not displayed is known as the VBI (vertical blanking interval), which contains certain signals which control the TV's scanning system and other functions.
720p: 720 lines of progressive video (720 lines per frame). Higher resolution than standard DVD (480i or 480p). Usually refers to 1280x720 resolution in 1.78 aspect ratio.
1/8" Mini plug (3.5mm): Mini plug used for computer, audio, and television connections can carry audio, video, and control functions.
1/4" Headphone (Microphone) plug (2.5cm): Bigger than the mini plug and was commonly used for microphone and head set connections. It has generally been replaced with the 1/8" mini plug on consumer electronics products.
12 Volt Trigger: Used to send to send control signal between components, generally to turn them on or off or raise and lower a projection screen.
75 Ohm Antenna Input: This connector is used today for TV reception for both cable and over the air signals. Screw on or push on F-Connector
300 Ohm Antenna Input: Double screw with flat antenna wire. Older TV's used this type of antenna connection.
A
A/B Speaker Terminals: Allows receiver to hook up 2 sets of speakers that can be played separately or both together.
Analog: A signal carried as a continuous waveform. NTSC TV system is an analog system.
Analog TV: Analog technology has been in use for the past 50 years to transmit conventional TV signals to consumers. "Standard" television broadcasts in analog TV. Analog signals vary continuously, creating fluctuations in color and brightness. Also known as NTSC - National Televison Standards Committee.
Audio Cables: Usually refers to a pair of Red and White color-coded RCA-type jack analog line-level audio connectors.
Audio/Video Cables: Sometimes called dubbing cables, but is tri-cable with Red, White, and Yellow RCA-type plugs. Yellow carries composite video and red/white carries analog audio.
AWG: American Wire Gauge, a measure of wire or cable thickness. Speaker cable is most measured this way. The gauge number gets smaller as the thickness of the wire increases, 18 gauge wire is thinner than 14 gauge wire.
AC-3: The multi-channel digital audio system developed by Dolby® and used by the new US DTV standard (also known as ATSC - Advanced Television Systems Committee). Also known as Dolby Digital®.
ADC: Analog to Digital converter is a device that converts the continuously varying value of an analog signal to a series of discrete values, represented by a binary number. The greater the size of this binary number the closer the digital signal obtained is to the original analogue signal. For example, a 1 bit number can only have 2 possible values; either 0 or 1 while an 8 bit number can have 256 different values, from 00000000 to 11111111
Anamorphic: Means "reshaping". A wide screen (16x9) picture occupying the entire screen of a standard 4x3 television, without a letterbox's black areas. This distorts the shape of the picture, making objects appear thin and tall.
ANSI: American National Standards Institute
Aspect Ratio: A numerical expression of the relationship of width to height of a TV screen. 4:3: This numerical sequence refers to the aspect ratio of the National Television Systems Committee (NTSC) TV screen, with "4" unit width corresponding to "3" unit height, proportionally, regardless of the actual size of the screen. 16:9: This numerical sequence refers to the aspect ratio of wide screen DTV formats for all HDTV and some SDTV (Standard Definition) video. A "16" unit width corresponds to "9" unit height proportionally, regardless of the actual size of the screen. The widescreen 16:9 numerical sequence provides a viewing experience very similar to that of most film motion pictures. Sometimes aspect ratio is expressed as the result of the aspect ration division - 16:9 equals 1.78 (16 divided by 9).
ATSC: An acronym for Advanced Television Systems Committee, and the name of the digital TV system used by broadcasters in the U.S.
ATV: Advanced Television was the FCC's term for the range of new television transmission technologies (including HDTV) considered for establishment in this country, but the acronym has been superseded by DTV (digital television).
B
Banana Plugs: Used on the end of speaker wire to connect to a receiver/amps and speaker. These plugs look like banana, thus the name, by being thick in the middle and narrow at the ends. This configuration gives very snug secure connection for audio equipment.
Barn Doors: A term used in television production to describe the effect that occurs when a 4:3 image is viewed on a 16:9 screen. When this happens, viewers see black or grey bars on the sides of the screen or "barn doors."
Binding Post: Speaker terminals that can accept a variety of end plugs even bare speaker wire.
BPS: Bits per Second, Often called the bit rate which is a measurement of the rate of flow of information. Each bit represents a single item of information; either a 0 or a 1. This is the basis of digital technology. The higher the bit rate, the greater the bandwidth required to transmit the information.
C
Characteristic Impedance: A way of measuring a cable or wires resistance to current while assuming the wire is of infinite length.
COFDM: Coded Orthogonal Frequency Domain Multiplexing is a modulation technology used for digital TV broadcasting in Europe.
Coaxial: A shielded copper wire cable that has a RCA plug or F connector. Can be used for digital as well as analog signal movement.
Codec: This term is short for "Coder-decoder." A codec is a device that converts analog video and audio signals into a digital format for transmission. It also converts received digital signals back into an analog format.
Component Video: A direct analog video connector that separates three different parts of the video signal, a brightness signal and two color-difference signals, usually with RCA-type connectors, color-coded red, green, and blue. Better than S-Video, composite, or RF-modulated video signal in the analog domain. May be labeled YPbPr, YCbCr, Y B-Y -Y, or YUV. Used to connect high bandwidth signals from digital sources, DVD, STB, D-VCR, to a Digital TV. Technically, it can be used to describe any video signal that is broken into components.
Composite Video: A video connection that has Y (Brightness) and C (Chrominance/Color) combined and must be processed by a comb or notch filter before the signal can become a picture image on a TV screen. Usually, represented by a yellow colored plug.
Compression: Compression refers to the reduction of the size of digital data files by removing redundant and/or non-critical information ("data" being the elements of video, audio and other "information"). Digital TV in the U.S. would not be possible without compression. The compression standard used in DTV in the ATSC system is MPEG-II.
Computer Input: Some HDTV sets have an input referred to as a VGA input. This is a misnomer - the input is normally a D-Sub miniature jack that carries a RGB computer signal that is used to connect computers to monitors.
Computer Signal Formats (normally with a RGB connector):
- VGA: A video graphics resolution of 640x480 pixels.
- SVGA: A video graphics resolution of 800x600 pixels.
- XGA: A video graphics resolution of 1024x768 pixels.
- WXGA: A video graphics resolution of 1366x768 pixels.
- SXGA: A video graphics resolution of 1280x1024 pixels.
- UXGA: A video graphics resolution of 1600x1200 pixels.
- QXGA: A video graphics resolution of 2048x1536 pixels.
D
Datacasting: Also known as "enhanced TV." Datacasting is the act of providing enhanced options offered with some digital programming to provide additional program material or non-program related resources. This allows viewers the ability to download data (video, audio, text, graphics, maps, services, etc.) to specially equipped computers, cache boxes, set-top boxes, or DTV receivers.
DAC: Digital/Analog (D/A) converter is an electronics component that convert digital signals to analog signals. This is used in DVD players and audio/video receivers to convert the digital input signal into an analog output signal that can be used to produce sound using speakers.
DBA-25: Multi-pin connector that carries 5.1 channel analog line-level signals; used in THX equipment.
DBS: The idea of Direct Broadcast Satellite was introduced with fanfare in the early 1980s and became reality in the 1990s. This is a system of directly broadcasting signals from satellites to consumers. Two commercial services are now distributing a cable-like menu of TV channels nationwide. Subscribers use small satellite dishes to receive the signal from high-powered satellites.
Decoder: See "codec." A device or program that translates encoded data into its original format (i.e., it decodes the data.)
Digital: Digital refers to the method of transmitting information in the binary system of 1's and 0's, and electrically are represented in circuits as two voltage levels, corresponding to 1 or 0.
Digital Cable: A service provided by many cable providers, digital cable offers viewers more channels. Contrary to many consumers' beliefs, digital cable is not the same as High- Definition Television or digital television; rather digital cable simply sends channels as digital signals on the cable.
Digital Monitor: This is a monitor that can display digital signals. In some cases it may be used to describe a monitor that uses digital technology, such as LCD or plasma.
Digital Television (DTV): Digital TV is the umbrella term encompassing High-definition Television and several other applications, including Standard Definition Televison, datacasting, multicasting and interactivity.
Digital Tuner: A digital tuner serves as the decoder required to receive and display digital broadcasts. It can be included inside TV sets or via a set-top box.
DSL: Digital Subscriber Line is a recent technology that speeds up the transmission of data on an ordinary phone line, permitting broadband services to offices and homes within a short distance of a telephone company central office.
DLP: Digital Light Processing® is a proprietary Texas Instruments technology that uses micro-mirrors on a chip to switch light for video projection, including digital televisions. This is a competing technology for LCD-based projectors.
Dolby® Labs: Dolby® Laboratories Laboratories is a developer and innovator in audio entertainment. Established by Ray Dolby, the company first developed noise reduction systems to improve recorded sound quality.
Dolby® Digital: Delivers mono, stereo, or up to 5.1 discrete channels of surround sound: Left, Center, Right, Left Surround, Right Surround, and low-frequency effects (LFE). Global standard for DVD-Audio and DVD-Video. Digital audio standard for North American HDTV, digital cable, and DBS systems. Optional audio format for most digital video broadcast (DVB) applications worldwide.
Dolby® Digital EX: Creates a rich surround-sound home theater experience by adding a sixth channel (Center Back) to Dolby Digital Surround EX™-encoded content for enhanced localization of surround effects.
Dolby® Pro-Logic: The Dolby® technology that made home theater possible. Decodes Dolby® Surround movie content into four playback channels of surround sound: Left, Center, Right, and Surround.
Dolby® Pro-Logic II: Transforms any high-quality two-channel source into five independent full-range channels: Left, Center, Right, Left Surround, and Right Surround. Brings new life to playback of CDs, MP3s, and other stereo content including surround encoded broadcast/VHS.
Dolby® Surround: The original Dolby® multichannel analog film sound format that revolutionized movie soundtracks. This technology encodes four channels of audio (Left/Center/Right/Mono Surround) on to just two audio tracks for media such as TV broadcasts and feature films on VHS. Material encoded in Dolby® Surround is fully compatible for playback on mono and stereo systems, and upon playback on systems containing Dolby Pro Logic® technology, the audio is reconstructed to its original four-channel surround sound.
DTV: Digital television. A TV transmission techniques using digital bit streams (a series of 0's and 1's) rather than analog waves with constantly varying values systems in radio frequency transmissions. A catch-all acronym used for the US ATSC broadcasting system. HDTV, EDTV, and SDTV are all forms of DTV.
DTCP: Digital Transmission Copyright Protection, a copy protection system, that controls copying of certain content. This system allows content to be categorized into three different categories - Copy Freely, Copy Once, and Copy Never. This system is most commonly used on the IEEE 1394 connection interface. Unlike HDCP, which prevents all copying, DTCP, also known as 5C, allows consumer copying of most digital content historically recordable in the analog world.
DTS: Digital Theater Systems, a digital sound treatment format of alternative encode/decode for surround sound home theaters and movie theaters. A competitor of Dolby® Digital. On DVD's some of the video information bandwidth is used for enhancing the audio.
DTVLink: This is an acronym for a CEA standard for connecting digital cable boxes and other products such as DTV's together using the IEEE 1394 (Firewire) interface. This standard ensures that products that carry the logo can interconnect and operate. This standard includes special software which is in addition to the standard IEEE 1394 interface, as well as DTCP.
DVD: The Digital Versatile Disk is similar to a CD but with 4.7GB storage capacity as compared with 650MB (0.65 MB) on a CD. It is capable of 133 minutes of video/audio playback. More complex, multi-layered versions are also available with a capacity of up to 17 GB for a 2 layered, double sided disc.
DVI: The "digital video interface" standard developed by the Digital Display Working Group (DDWG). DVI may be a replacement for analog VGA monitor interface as well as standard component video. The DVI signal is actually digital component video, and has the same performance as standard component video. Sometimes the DVI interface includes HDCP - High-Definition Copy Protection, which prohibits all ability to record or copy the content.
E
EDS: Enhanced data services provide additional information in VBI part of the NTSC scanning signal such as a time signal. Also, called XDS (Extended Data Service). Commonly used to send time information to VCR's, as well as program data to some EPG systems.
EPG: An Electronic Program Guide on a cable system, a DBS service or in DTV permits a viewer to choose a program from a menu and be switched to the appropriate channel automatically.
EDTV: EDTV stands for Enhanced Definition Television, which is an industry recognized form of DTV. The EDTV format is essentially 480 lines of resolution in progressive scanning, or 480p (the "p" stands for progressive scanning). The complete Digital TV standard consists of no less than 18 different picture formats, but only three formats are commonly used - HDTV, EDTV and SDTV.
F
FCC: The Communications Act of 1934 created the Federal Communications Commission as an independent agency to regulate interstate communications.
Fixed Output: An audio output whose signal cannot be adjusted by the volume control.
Fixed Pixel Displays: Fixed Pixel Displays: LCD's, PDP's and DLP's are examples of fixed pixel displays. These display devices have actual pixels (picture elements) that make up the display. Unlike CRT and scanning devices, FPD's have clearly measurable display resolution - just count the pixels.
Firewire: See IEEE1394
H
HAVI: Stands for Home Audio Video Interoperability. This is a software standard based on the IEEE 1394 connection, that allows connected devices to transmit their status and control codes to other devices. For example, a D-VHS connected to a television would send to the TV it's control codes, so the TV could control the D-VHS HD VCR, with the OSD. This is an enhancement of the basic software used in the IEEE 1394 interface.
HDCP: High Definition Copy Protection is a scrambling system used on DVI and HDMI connects to protect content by prohibiting all recording/copying of the content.
HDMI: High Definition Multimedia Interface is a new connector that combines DVI signals, and digital audio into one small connector, allowing for simple and easy connections between a source device and a display. HDMI is somewhat backward compatible with DVI, by using a convertor plug. HDMI often also includes HDCP copy protection.
HDTV: High Definition Television is the highest performance segment of the DTV system used in the US. It's a wide-screen, high-resolution video image, coupled with multichannel, compact- disc-quality sound. HDTV is one of the three basic forms of DTV - also see EDTV and SDTV.
HTML: Hypertext Markup Language is a simple coding of text on a web page that displays it on a browser. When a user clicks on a coded hypertext link, it causes the browser to call up another specified web page.
Hz: short for Hertz or cycles per second. Hz is a unit of measure of the frequency
I
IEEE 1394: A standard for transmission of digital data between external peripherals, including consumer audio and video devices. IEEE 1394 is a serial bus similar in principle to USB and transferring data at up to 400Mbps. With its high data-transfer speed and "hot plug-and-play" capability, IEEE 1394 can interface with digital audio and video devices, as well as external hard drives and other high-speed peripherals. Unlike other connections between products, IEEE 1394 also provides control software protocols, so that connected devices can control each other easily. IEEE 1394 was invented by Apple, which calls it FireWire. Sony refers to this interface as i.Link.
IEEE: Institute of Electrical and Electronics Engineers is an electronics standards body.
Interlaced Scanning: This process divides and presents each video frame as two fields, which form a frame. Imagine a video frame being divided by the odd and even horizontal lines that make up the picture. The first field presents the odd lines; the second field represents the even lines. The fields are aligned and timed so that, with a still image, the human eye blends the two fields together and sees them as one.
J
JPEG: Joint Photographic Experts Group is the international committee which created its namesake standard for compressing still images.
L
Letterbox: Letterbox refers to the image of a wide-screen picture on a standard 4:3 aspect ratio television screen, typically with black bars above and below. It is used to maintain the original aspect ratio of the original source (usually a theatrical motion picture of 16:9 aspect ratio or wider).
LFE: Low frequency effects refers to the deep bass effects that represent the ".1" of the "5.1" channel surround sound. It makes explosions more explosive, and gives the foot stomps of the dinosaurs in "Jurassic Park" and "Godzilla" a more terrifying effect. To fully realize the impact of low frequency effects, subwoofers are usually recommended. However, if you have main speakers that can reproduce frequencies down to about 20-30 Hz, you may find that adequate for your needs, particularly if your receiver can divert the LFE signal to the main speakers.
M
MHz: Megahertz – one is equal to 1,000 Hertz, or 1,000 cycles per second – is the measure used to indicate the frequency of an FM or TV channel. The bandwidth of the channel, from the top frequency to the bottom, is also measured in megahertz.
Monitor: A video display device that shows an image from an unmodulated or non-RF signal.
MPEG: Motion Pictures Expert Group is an international standards-setting body that has specified standards for digital audio and video recording, among other things. MP3 is the most famous audio standard specified by the organization.
MPEG-2: Motion Picture Expert Group. This is the standard being employed by digital television and DVD for compression of both audio and video and uses a DCT algorithm.
MTS: Multi-channel Television Sound, the official name of the standard for stereo analog television broadcasting, invented by Zenith. Usually includes dbx noise reduction and always has SAP.
Multicasting: The option to multicast was made possible by digital technology to allow each digital broadcast station to split its bit stream into 2, 3, 4 or more individual channels of programming and/or data services. (For example, on channel 7, you could watch 7-1, 7-2, 7-3 or 7-4.)
Must-carry: This refers to the legal obligation of cable companies to carry analog or digital signals of local over-the-air broadcasters.
N
NAB: The National Association of Broadcasters is the television and radio industry's primary lobbying and trade organization. It largely represents the interests of commercial broadcasting, though 400 of its 6,000 members a republic broadcasting organizations.
Nominal Impedance: Speaker specification that describes a speaker's resistance to current and the load it presents to an amp.
NTSC: NTSC is the acronym that stands for "National Television Systems Committee" and the name of the current analog transmission standard used in the U.S., which the committee created in 1953.
O
Optical: Usually refers to a digital audio connector using fiber-optic cable.
P
PCM: Pulse Code Modulation, Refers to an optical or coaxial digital connection carrying CD-type and other low-resolution audio. PCM is a type of digital audio that can be low-resolution (CD) or high-resolution (DVD-Audio).
PBS: The Public Broadcasting Service was formed in 1969 to distribute public TV programming nationally. PBS operates these program distribution services: NPS (National Program Service), SIP (Station Independence Program, for fundraising specials), ALS (Adult Learning Service, for college telecourses), PBS Select (individually syndicated programs) and PBS Plus (fully underwritten programs).
PIP: Picture in picture is a feature of some televisions that shows another channel or video source in a small window superimposed in an area of the screen.
POP: Picture outside picture. A feature of some wide screen displays that uses the unused area around a picture to show additional pictures.
Pillarbox: maintains an image's original aspect ratio. However, this technique is used when watching a 4:3 image on a 16:9 screen. The bars are placed on either side of the image, instead of above and below. It should be noted that some televisions "stretch" the 4:3 image to fill the screen. While this would remove the unsightly black bars, everyone on the screen would appear to be rather overweight!
Pixels: The small 'dots' which make up all television screens. Each is a discrete element of the picture, but when viewed from a distance the pixels are small enough that they blend into one another to create a smooth picture. Stands for "Picture Element".
Progressive Scan: The TV image is drawn or refreshed from top to bottom of the picture progressively (1 line after another). Progressively scanned images must be scanned faster than interlaced, to avoid the viewer "seeing" only part of the picture, instead of a full frame.
PSIP: Program and System Information Protocol is a section of the ATSC digital data stream that allows program suppliers and DTV broadcast stations to name, describe, and provide schedules and information about DTV programs. PSIP can also be used to program DTV receivers to refer to broadcast channels by their native or original broadcast channel number even though they're actually broadcasting on another channel. NOTE: Some DTV receivers have the ability to use the PSIP data to rename a broadcast channel to its native channel and some don't. Generally, the early model receivers did not have this ability but the more recent models now do. This could be confusing to some people, but it's intended to make it easier for viewers to find their favorite stations and enable broadcast stations to maintain their brand identity.
Q
QAM: Quadrature Amplitude Modulation. A modulation scheme which is used either on its own (in cable transmission) or with COFDM. QAM Clear is unscrambled cable broadcast signal. Scrambled QAM is scrambled Premium and/or Pay per View cable broadcast.
QPSK: Quadrature Phase Shift Keying. A modulation scheme which is used in satellite transmission. It can also be combined with COFDM.
R
RCA Plug: Connectors using the quarter-inch wide plug and jack invented by RCA Labs. RCA jacks are widely used in audio and video gear both for analog and digital video and audio.
RF: Radio Frequency refers to the transmission of a signal through the air or cable as a electromagnetic field. Broadcast television, cable television and satellite television, as well as radio - both terrestrial and satellite use radio frequency to broadcast their signals.
RGB: RGB stands for red, green, blue, and is a form of an electrical baseband video signal used by computers and some HD equipment. While it is technically a component video signal, to avoid confusion is it not referred to that way. It can be analog or digital.
RGB+HV: A RGB signal where the synchronization impulses that keep the picture fully synchronized (all colors at the right time) are found in separate cables. RGB has three "wires" and HV add two more "wires."
S
SAP: The Separate Audio Program channel, a secondary capability of stereo television transmissions, allows TV broadcasters, including PBS and public TV stations, to deliver a second soundtrack for enhanced services such as second-language soundtracks or DVS (Descriptive Video Service). Only stereo TV sets containing SAP decoders are capable of receiving SAP audio. (Look for the little SAP switch on the control panel.)
Standard Definition TV Format (SDTV): The lowest performance level of the three basic formats of DTV. SDTV has about the same picture resolution (detail) as today's analog television, but may appear clearer since it does not suffer from analog interference. Also see EDTV and HDTV.
SECAM: Séquential Couleur Avec Mémoire/Sequential Color with Memory. A composite color standard similar to PAL is currently used only as a transmission standard in France and a few other countries. The video is produced using the 625/50 PAL standard and is then transcoded to SECAM by the player or transmitter.
Set-top Converter Box: This unit sits on top of the viewer's analog TV, receives the Digital TV signal, converts it to an analog signal, and then sends that signal on to the analog TV.
SMPTE: The Society of Motion Picture & Television Engineers is an organization of visual arts professionals that works to establish technical standards for lighting, equipment and film. SMPTE was founded for the movie industry as SMPE in 1916.
S/PDIF: Sony/Philips Digital Interface, a digital connection used in receivers and other digital audio/video products. May be optical or coaxial.
STB: Set-top box a multi-purpose box that sits on top of your TV and may decode satellite TV, unscrambles encrypted cable TV, or decodes digital TV signals.
Stereo: Two channel audio signal which originally was called Stereophonic. Home Theater systems are multi-channel sound system, but can be switched to 2 channels stereo.
Subwoofer: A speaker, usually with internal amplification, that produces only low frequency sounds, known as bass. See LFE.
Super Video Graphics Array (SVGA): This acronym is short for the "Super Video Graphics Array" display mode. SVGA resolution is 800 x 600 pixels.
S-Video: A baseband video connection that keeps the brightness (Y) and color (C) parts of the video signal separated. A multi-pin connector, sometimes, called a Y/C plug.
T
Terrestrial Broadcasting: This is a broadcast signal transmitted "over-the-air" to an antenna.
Toslink: Official name of digital optical cable with plastic vs. glass filament.
U
Upconverting: Process by which a lower-resolution signal is converted to a higher-resolution signal. It appears "softer" than a true higher-definition image. It is not possible to make a low-resolution signal have all the resolution of the higher-resolution signal, since this detail is not in the low-resolution signal.
URL: The Uniform Resource Locator is the Internet address of a web page, image or other file on the Internet.
W
Widescreen: A term given to picture displays with a wider aspect ratio than NTSC 4:3. Digital HDTV or SDTV is referred to as "16:9 wide screen." Most motion pictures also have a 16:9 wide screen aspect ratio. Most Digital TVs have a screen that is wider than it is tall (if a Digital TV screen is nine inches high, it's 16 inches wide.) When watching a show recorded in the wide screen format on a Digital TV, viewers see more of the movie, while when viewing wide screen format on an analog TV, cropped edges are evident.
V
Varible Output: An audio output adjustable through the volume control.
VBI: The Vertical Blanking Interval is a portion of the TV signal that carries, instead of picture or sound, such additional information as closed captioning, stock prices and other data. The VBI consists of the first 21 lines of each of the two interlaced fields that make up the TV picture. Line 21 is designated to carry captioning data.
Video Graphics Array (VGA): This acronym is short for the "Video Graphics Array" display mode. VGA resolution is 640 x 480 pixels.
Video: The information used to create a picture on a TV or sometimes referring to composite video connections.
VOD: Video on demand is a service that some observers believe will add nearly limitless variety to cable and other addressable delivery platforms. The viewer can choose a program among many on a long menu and see it at any time.
VSAT: Very Small Aperture Terminal is a two-way satellite technology that transmits and receives computer data and other narrow-bandwidth material. In the reconstruction of public TV's satellite system, PBS acquired VSAT equipment for all public TV stations to give them interactive capability, but the Internet now plays that role.
VSB: 8-VSB (8 Level Vestigial Side Band) is the modulation system created by Zenith and chosen by the industry-wide Advisory Committee on Advanced Television Service, recommended by ATSC and adopted by the FCC for DTV broadcasting in the U.S. It is now the foundation of the ATSC broadcast standard.
X
XLR: A connector using a 3 pin jack or plug. It carries line level audio signal for long distances, and is used in professional applications or high-end home stereo systems.
Y
Y/C: A video connection that has two separate signals Y (luminance/brightness) from C (chrominance/color). See S-Video.

Portions of this glossary were provided by the FCC.