Sources:

• Adobe Glossary of Digital Video Terms, an extensive compilation of terms related to digital video.
• Webopedia, an online dictionary and search engine geared toward computer and Internet terminology

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analog
A video signal made of a continuous electrical signal. Your television and VCR can be analog video devices. To be stored and manipulated on a computer, analog video must be converted to digital video.

AVI
Abbreviation for Audio-Video Interleaved; the algorithm created by Microsoft for synchronizing and compressing analog audio and video signals. AVI is also the file format used by Video for Windows

bandwidth
(1) The frequency range of a video signal in MHz. (2) The amount of information that can be carried by a signal path. Similar to the amount of water that can be carried by a pipe of a specific diameter.

capture card (video capture card)
Sometimes called a capture or video board, the logic card installed into a computer and used to digitize video. Or, for video that is already digitized, the device that simply transfers the file to the hard disk. Using a hardware or software codec, the capture card also compresses video in and decompresses video out for display on a television monitor.

capturing
Refers to the process of transferring video from one media source (e.g.: VHS tape, digital video camera) for use on a computer. If analog, the captured video is converted to digital.

CD
Abbreviation for compact disc; the digital data storage media proposed by Philips and Sony. CD is the preferred medium for storing digital multimedia files because it is inexpensive and has a fairly large capacity (640 MB).

CD-ROM
Abbreviation for compact disc read-only memory; A CD that cannot be written to.

CD-R
Compact disk that can be used for storing digital media, often referred to as writeable CD's. Data can only be written or burned on the CD once.

CD-RW
Compact disk that can be used for storing digital media, often referred to a re-writeable CD's. Data can be written or burned on the CD multiple time.

Cinepak
A commonly used QuickTime codec for compression of video files on CD-ROM. Cinipak offers temporal and spatial compression, and data-rate limiting.

codec
Contraction of compression/decompression algorithm; used to encode and decode, or compress and decompress data, such as sound and video files. Common codecs include those that convert analog video signals to compressed digital video files (e.g., MPEG), or that convert analog sound signals into digital sound files (e.g., RealAudio).

compression
The translation of audio or video data into a format that requires less storage space than the original data. See also, codec.

converter box
Hardware used to convert an analog signal to digital format for use on a computer.

data rate
The amount of data moved over a period of time, such as 10MB per second. Often used to describe a hard drive's ability to retrieve and deliver information.

digital
information in the form of binary data. Computers are digital machines that use a binary system. That is, at their most basic level, computers can distinguish between just two values, 0 and 1 (i.e, off and on). There is no simple way to represent all the values in between, such as 0.25. All data that a computer processes must be digital, encoded as a series of zeros and ones. Digital representations are approximations of analog events. They are useful because they are relatively easy to store and manipulate electronically.

digital video
A video signal made of binary digits. To store and manipulate analog video on a computer workstation, it must be converted to digital video.

DV
See digital video

DVD
Abbreviation for digital versatile disc. DVDs look like CDs, but have a much larger storage capacity—more than enough for a feature-length film compressed with MPEG-2. DVDs require special hardware for playback.

DVD-ROM
A digital storage medium based on DVD that may eventually replace CD-ROM.

Firewire
The Apple Computer trade name for IEEE 1394.

fps (frames per second)
Abbreviation for frames per second; the standard for measuring the rate of video playback speed. A rate of 30 fps is considered real-time speed and a rate of 24 fps is considered animation speed. At 12-15 fps, the human eye can detect individual frames causing video to appear jerky.

frame
A single still image in a sequence of images that, when displayed in rapid succession, creates the illusion of motion. The more frames per second (fps), the smoother the motion appears.

frame rate
The number of frames per second displayed during playback.

HTTP
Short for HyperText Transfer Protocol, the underlying protocol used by the World Wide Web. HTTP defines how messages are formatted and transmitted, and what actions Web servers and browsers should take in response to various commands. For example, when you enter a URL in your browser, this actually sends an HTTP command to the Web server directing it to fetch and transmit the requested Web page.

IEEE 1394
The interface standard that enables direct transfer of DV between devices, such as a DV camcorder and a computer. IEEE 1394 also describes the cables and connectors utilizing this standard. (Also called FireWire)

Media 100
A non-linear editing system that uses its own properitary software. Often used with Adobe After Effects.

MPEG-1
The international compression standard for the conversion of analog motion video to digital motion video that includes both video and audio data. MPEG meets the needs CD-ROM and video-on-demand applications. Actual compression over uncompressed digital video is about 100:1. MPEG-1 was initially designed to deliver near-broadcast quality video through a standard speed CD-ROM. Playback of MPEG-1 video requires either a software decoder coupled with a high-end computer or a hardware decoder.

MPEG-2
MPEG-2 is an extension of the MPEG-1 compression standard designed to meet the requirements of television broadcast studios. MPEG-2 is the broadcast quality video found on DVDs and requires a hardware decoder (e.g., a DVD-ROM player) for playback.

multimedia
The combining of different computer-based media—usually audio, text, graphics, and animation—into a single presentation. Multimedia presentations are typically played back directly from the computer.

non-linear
Random-access editing of video and audio on a computer, enabling edits to be processed and reprocessed at any point in the timeline, at any time. Traditional videotape editors are linear because they require editing video sequentially, from beginning to end.

NTSC
National Television Standards Committee. The acronym refers both to the committee and to the standard video signal format used in the United States. NTSC delivers 29.97 frames per second. Also referred to as composite.

PAL
Phase Alternation Line. A signal format used in video equipment in Europe and parts of Asia. PAL signals give you 25 frames per second, and so are incompatible with NTSC, the American video signal format.

plug-in
A software module that extends the features of and can be used within a software application.

Quicktime
Apple Computer's multi-platform, industry-standard, multimedia software architecture. QuickTime is used by software developers, hardware manufacturers, and content creators to author and publish synchronized graphics, sound, video, text, music, virtual reality, and 3-D media. QuickTime 4 includes support for Real Time Streaming Protocol (RTSP). For more information: http://www.apple.com/quicktime

RealMedia
Architecture designed specifically for the Web, featuring multimedia streaming and low data-rate compression options. RealMedia works with or without a RealMedia server. For more information: http://www.real.com/

RTSP
Short for Real Time Streaming Protocol, a proposed standard for controlling streaming data over the World Wide Web. RTSP uses RTP (Real-Time Transport Protocol) to format packets of multimedia content. RTSP is designed to efficiently broadcast audio-visual data to large groups.

streaming
The process of sending video over the Web or other networks to allow playback on the desktop as the video is received, rather than requiring the entire file to be downloaded prior to playback.

Surestream - Technology created by RealSystems that allows you to create files that support multiple bandwidth connections within one clip. Using the RealPlayer, users can designate a preferred bandwidth speed and Surestream can deliver a version of the clip optimized for that particular speed.

uncompressed video
Raw digitized video displayed or stored in its native size.

VHS
Abbreviation for Video Home System; the consumer video cassette recorder that uses a 1/2-inch tape.

video
1) A means for reproducing moving visual images by representing them with an analog electronic signal. The images are decomposed into a series of horizontal scan lines. In this way the signal can be stored, transmitted and reproduced. (See rasterization, field, frame.) (2) There are various standards that define this signal, See NTSC, PAL, SECAM, RGB. (3) Referring to the NTSC composite video standard. This is a widespread standard such that the video in of one machine is compatible with the video out of another.