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The traditional format in which audio and video are transmitted by using a wave or analog signal. An analog signal may not work with digital speakers; computers use digital signals.

anchor window

A small window that appears in the lower-right corner of the screen when Windows Media Player is in skin mode, which enables you to return to full mode.



The transmission method used by a radio station (AM, FM, or Internet).


The data transfer capacity of a digital communications system, such as the Internet or a local area network (LAN). Bandwidth is usually expressed in the number of bits that a system is capable of transferring in a second: bits per second (bps) or kilobits per second (Kbps).

bit rate

The speed at which digital audio and video content must be streamed to be rendered properly by a player; or the speed at which digital content in general is streamed on a network. Bit rate is usually measured in kilobits per second (Kbps), for example, 28.8 Kbps.


A high-speed transmission. The term generally refers to communication lines or services that operate at T1 rates (1.544 Mbps) or higher.


An area of computer memory reserved for temporarily holding data before that data is used on the receiving computer. Buffering protects against the interruption of data flow. Buffered data is instantly available to computer programs running on the computer where the buffer is located.


call sign

The identifying code letters or numbers of a radio or television transmitting station, assigned by a regulatory body.


Text that accompanies images or videos, either as a supplemental description or a transcript of spoken words.


See definition for: compact disc (CD)

CD burner

See definition for: CD recorder

CD recorder

A device used to write files to recordable compact discs.


See definition for: compact disc-recordable (CD-R)


See definition for: compact disc-rewritable (CD-RW)


In a DVD, a portion of a title, such as a scene or sequence. A title can contain one or more chapters.

See also: title


An abbreviation for compressor-decompressor. It is software or hardware used to compress and decompress digital media.

compact disc (CD)

An optical storage medium for digital data, usually audio. A compact disc is a nonmagnetic, polished metal disc with a protective plastic coating that can hold more than 1 hour of recorded audio.

compact disc-recordable (CD-R)

A type of compact disc on which files can be written.

compact disc-rewritable (CD-RW)

A type of compact disc on which files can be written multiple times.


The coding of data to reduce file size or the bit rate of a stream. Content that has been compressed is decompressed for playback.

Compression Quality

In Windows Media Player, a setting that determines the sound quality of the digital audio as the data is copied to a computer or portable device or streamed to the Player.

connection speed

The speed at which data is transferred between a network and a computer.

content provider

The person or organization that distributes Windows Media files (for example, a record, movie, or streaming media company). The content provider may also be the content owner.



To convert encrypted content back into its original form (clear content).

See also: encrypt


Data in ones and zeros that can be processed by computers.


To deliver or receive content over a network by copying the content to a computer on which it can be played locally. In contrast, when content is streamed, the data is not copied to the receiving computer.



To convert information into a specified digital format for convenient storage, retrieval, and delivery over a network. Compression and encryption technologies are often used in encoding.


To programmatically disguise content to hide its substance. Encrypted content, often called a cipher, cannot be played without first being changed back into its original form (clear content) through the process of decryption.

See also: decrypt

error correction

A method of controlling and correcting data transmission errors.


file format

The structure of a file that defines the way it is stored and laid out. The file format contains instructions and codes used by programs, printers, and other devices. The format of a file is indicated by its file name extension.

See also: file name extension, file type

file name extension

A set of characters added to the end of a file name that identifies the format of a file, the type of content it contains, and the type of program or device it can be used with, for example, .wma.

See also: file format

file type

A category that indicates the nature of the content of a file, usually identified by the file name extension. The file type determines which program can be used to play or open a file.

See also: file format


A system or combination of systems that enforces a boundary between two or more networks and keeps unauthorized users out of private networks. A firewall system checks all incoming and outgoing messages to be sure they meet predetermined security criteria.


In Windows Media Technologies, the type of music (genre), such as rock or classical, played by a radio station.


One of many sequential static images that make up video.

frame rate

The number of frames displayed per second in video. High frame rates generally produce better quality video because there are more frames, which makes movement in the video appear smoother.


In Windows Media Player, the value, such as 88.5 or 101.7, used to locate or identify a radio station.

full mode

The default operational state of Windows Media Player in which all of its features are displayed. The Player can also appear in skin mode.

See also: skin mode



See definition for: Hypertext Transfer Protocol (HTTP)

Hypertext Transfer Protocol (HTTP)

The Internet protocol used to deliver information over the World Wide Web.


licensed file

A Windows Media file that has an associated license that defines how the file can be played. The restrictions stated in the license vary depending on the license creator. When a CD track is copied by using Windows Media Player, a license can be assigned to the newly created file. Under that license, the file can only be played on the computer where the file was created.


Media Information

A feature of Windows Media Player that provides information, such as the album cover, label, artist name, and length, gathered from the Internet about a CD. An Internet connection is required to access this information initially.


See definition for: Musical Instrument Digital Interface (MIDI)

Moving Picture Experts Group (MPEG)

A set of standards for audio and video compression established by the Joint ISO/IEC Technical Committee on Information Technology. The different specifications, or layers, of MPEG are designed to work in different situations. For example, MPEG Audio Layer 3, or MP3, uses perceptual audio coding to compress CD-quality sound.


See definition for: Moving Picture Experts Group (MPEG)


A method of distributing content in which multiple clients share a stream from a server.

multiple bit rate

Describes a file or stream that contains the same content encoded at several different bit rates. As network traffic changes, a Windows Media server can switch to a lower or higher bit rate to optimize content delivery.

Musical Instrument Digital Interface (MIDI)

A standard protocol for the interchange of musical information between musical instruments, synthesizers and computers. It defines the codes for a musical event, which include the start of a note, its pitch, length, volume, and musical attributes, such as vibrato. It also defines codes for various button, dial, and pedal adjustments used on synthesizers.



A list of links to various digital media files on a computer, a network, or the Internet.


An interface through which data is transferred between a computer and other devices, a network, or a direct connection to another computer.

portable device

A computing device or storage card that is not a desktop computer. Examples of portable devices include computing devices such as Pocket PCs, and storage cards such as CompactFlash cards.


A set of formats and procedures that enable computers to exchange information. Protocols that Windows Media Technologies use include HTTP and MMS.

proxy server

A server located on a network between client software, such as a Web browser, and another server. It intercepts all requests to the server to determine whether it can fulfill them itself. If not, it forwards the request to another server.


root menu

See definition for: top menu



A file that customizes the appearance and functionality of Windows Media Player in skin mode.

skin mode

An operational state of Windows Media Player in which its user interface is customized and displayed as a skin. Some features of the Player are not accessible in skin mode. By default, the Player appears in full mode.

See also: full mode


A method of delivering content in which content located on a server is transmitted across a network in a continuous flow and then played by client software. By streaming data, a player can begin rendering the content immediately instead of waiting for an entire file to be downloaded.



See definition for: Transmission Control Protocol (TCP)


In a DVD, the largest unit of content, such as a movie or TV program. A DVD can contain one or more titles.

See also: chapter

title menu

Typically, the main on-screen menu of a DVD. It is frequently used to view specific titles, chapters, or supplemental material on a DVD, or to control subtitle, language, or other settings.

See also: top menu

top menu

Typically, the on-screen menu for a specific title on a DVD. It is frequently used to select specific chapters to be played within a title. Also known as the root menu.

See also: title menu


An individual song or other discrete piece of content from a CD.

Transmission Control Protocol (TCP)

The protocol within TCP/IP that governs the breakup of data messages into packets to be sent via IP, and the reassembly and verification of the complete messages from packets received by IP.



See definition for: User Datagram Protocol (UDP)

User Datagram Protocol (UDP)

A connectionless transport protocol in the TCP/IP protocol stack that, like TCP, runs on top of IP networks.



In Windows Media Player, a feature that displays audio as moving splashes of color and geometric shapes.


Windows Media file

A file containing audio, video, or script data that is stored in Windows Media Format. Depending on their content and purpose, Windows Media files use a variety of file name extensions, such as: .wma, .wme, .wms, .wmv, .wmx, .wmz, or .wvx.

Windows Media Format

The format used by Microsoft Windows Media Technologies (or a third-party product that incorporates a licensed Windows Media technology) to author, store, edit, distribute, stream, or play timeline-based content.

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