A Glossary of Distributed Digital Music Terms

AAC

(Advanced Audio Coding) The default audio encoding format for Apple; the iPhone, iTunes, and the iPod all use this. AAC is an encoding scheme using lossy compression. It is the successor to the MP3 format. For the most part it has better sound quality than MP3, but because of licensing issues hasn't seen as much uptake outside of Apple products. See also: FLAC, helix, MP3.

Aliasing

A kind of audio distortion caused by recording a high frequency sound at a low sample rate, resulting in a low pitch or buzz. The effect is similar to aliasing in graphics, when a digital image is blown up many times its original resolution and thus shows jagged stairsteps along sloped lines. Can be fixed by using an anti-aliasing filter to record the audio onto digital format; however, once a sound has been recorded with aliasing, it can't be fixed.

Analog

The opposite of digital. Examples of analog media storage include phonograph records, audio cassette tapes, video cassette recorder (VCR) tapes, and photographs taken on film. While computers have to represent an audio recording in digital form, which is actually just numerical data, analog storage devices can store audio as a frequency over a constant period of time, without the need to convert between the two. Thus, analog media always has a higher-quality playback, but computers are catching up so rapidly that most people can't tell the difference anymore. See also: Digital

APE Tag

A digital file standard used to include metadata in an audio file usually artist, title, and track. The spelling of APE would imply that it's an acronym, but it is in fact named after the Monkey's Audio format, which was the first to use it. Usually seen on Microsoft platforms. See also: CDDB

ASCAP

(American Society of Composers, Authors and Publishers) One of two US-based organization which polices the copyrights to performed works by monitoring public performances of these works. Typically they collect license fees on behalf of artists and distributes the royalties to them. See also: BMI, RIAA

BitTorrent

The peer-to-peer file sharing protocol that basically gave birth to the file sharing movement of the 21st century; some estimates indicate that BitTorrent traffic accounts for 35% of all Internet traffic. BitTorrent works by making each file-sharer responsible for passing pieces of the file on the the next file-sharer while they're still downloading, negating the necessity for one massive server for everyone to download from. See also: Leech, Seed

BMI

(Broadcast Music, Incorporated) The other one of two US-based organization which polices the copyrights to performed works by monitoring public performances of these works. Typically they collect license fees on behalf of artists and distributes the royalties to them. See also: ASCAP, RIAA

Broadband

Refers to a method of transmitting high-volume data communications. This can mean network or Internet data transfer over fiber optic cable as opposed to a telephone modem, or to the practice of splitting up data packets and sending them on multiple channels at the same time. It might also simply refer to signal capacity, all depending on context. Generally when a data transmission medium is referred to as "broadband", that means that it has a higher capacity for traffic. Think of a wide pipe as opposed to a straw.

Buffer

The memory used to temporarily store data when transmitting it between any two devices. Typically this means that while you stream audio from a downloaded source, it has to fill so much memory with the audio data to get a "head start" before your device plays, so that it can continue playing the audio while the rest is downloading without interrupting. Just like a big jug (the website) pouring into a small jug (your device memory the buffer) pouring into a funnel (your media player).

BWF

(Broadcast Wave Format) The extended version of the WAVE audio file format. Its purpose is to facilitate the exchange of sound data between two different computer platforms or applications, using metadata to accomplish this task seamlessly. See also: WAV

Capture

To record audio data in a digital device from any number of sources, including anything from an analog recording to a live performance. Typically done with a microphone.

CBR

(Constant Bit Rate) A rate of encoding an audio sample in which the capture rate remains consistent throughout the file. This results in an unnecessarily large file size a single flute playing takes up as much file space as an entire orchestra playing. See also: VBR

CD Burner

A device on which a compact disk may be recorded with data. Both CDs and DVDs are counted as optical disk mediums, since the data is recorded onto them by burning small pits into the plastic disk which may then be read with a laser light. A CD-burner may refer to a CD-RW drive, or the software used to record the data using the drive.

CDDB (Compact Disc Data-Base)

On online database of music CD metadata. Typically deployed in CD-using audio players, where the player downloads the metadata in order to provide the artist, album name, track list, and so on. See also: APE Tag

Coaster Toaster

A common slang term for a CD-RW device. Refers to the similarity between a compact disk and the coaster you set your drink on, and the fact that burning a CD makes it warm to the touch afterwards, like toast. See also: CD-Burner

Codec

(an abbreviation for "coding/decoding") A method for encoding and decoding data in order to transmit or share it with another device. Codecs act like standards; without them, no data could be shared from one electronic device to another. Whether or not a file will play on your device depends on whether your device is equipped to handle that file's codec. See also: Transcode

Copy Protection

The method of preventing a creative work from being copied from one unit of storage to another, by embedding protection devices in the media itself. Frequent methods include watermarking images, having a CD-key for a purchased software program which must be typed in before the program will install, and playback-protection software included on an audio CD to prevent a computer from playing it. Like DRM, copy protection in media is also fraught with drawbacks, difficulties, and failures. See also: Copyright, DRM, Rootkit

Copyright

An instrument of law in which the creator or current owner of a creative work is enabled to exercise their intellectual property rights over that work. Copyright laws, internationally, have been thrown into a state of upheaval due to the digital file-sharing revolution, which introduces questions that copyright laws were never intended to answer. See also: Creative Commons, Public Domian, DRM

Creative Commons

A non-profit organization which facilitates the licensing of creative works in a more liberal manner than traditional copyrights. Artists may release their work under various Creative Commons licenses, specifying that a work may be either given away for free, resold, or even altered or sampled for derivative works. See also: Copyright, Indie, Public Domain

Digital

The opposite of analog. A digital storage medium is one which encodes the analog input as data; the audio is stored not as frequencies, but as pure numbers. Because computers can only handle bits of numerical data, all media forms, be they images, sounds, or video, must be converted into digital form to be stored and processed, then when the file is viewed or played it must be reconverted to an analog signal to send to the output device. See also: Analog

DRM

(Digital Rights Management) The methods deployed by copyright holders, publishers, and hardware manufacturers to attempt to control access to copyrighted media. DRM has been the source of immense controversy amongst file-sharers of every media, and music file-sharers in particular. Problems with DRM include the fact that DRM may be circumvented through various means, that it might prevent a legitimate customer from using media they legally own in the way they want to, and that DRM-protected media is not easily transferred from one device to another once a device becomes obsolete. Further issues have included unintended bugs and errors in DRM systems. See also: Copyright, Copy Protection, Fairplay, PlaysForSure, Rootkit

Fairplay

A DRM system deployed by Apple, Incorporated. It is a system of digital encryption which prevents the protected file from being played on an unauthorized device. It is built into the QuickTime video and audio format, as well as into iPods, iPhones, and files sold through iTunes. Apple has announced that as of 2009, it would discontinue Fairplay, however, Apple still deploys DRM methods in all of its media transactions. See also: DRM

Firewire

(Also known as "IEEE 1394 interface") A serial bus interface communication protocol, used to send and receive data on computers as well as audio and video devices. In spite of the name, Firewire is not restricted to wires, but is a protocol (just like http) that can be used over wireless, fiber optic, and coaxial networks.

FLAC

(Free Lossless Audio Codec) A free and open source file format featuring lossless audio data compression. It was created to provide an open alternative to the patented MP3 and AAC formats. Because it is licensed under the GNU General Public License, it is widely deployed in both hardware and software across Microsoft, Apple, and Unix-like platforms. The Xiph.Org Foundation, a non-profit organization, maintains and makes available a wide variety of support software. See also: AAC, Helix, MP3

Flash

A media-capable portable platform. Flash, originally produced by Macromedia and later bought by Adobe, is a technology that combines audio and graphics handling with a scripted programming language known as Actionscript, to create an embedded portable platform similar to Java. Flash is usually the format of choice for streaming audio. See also: Streaming Audio

Helix

A free and open source project which is aimed at producing software which can play multiple media formats across multiple platforms, started by the RealNetworks company. the aim is to run on every device from a desktop computer to a mobile phone. See also: AAC, FLAC, MP3

Indie

Common slang abbreviation for "independent", referring to independent artists as opposed to studios and major producers. The "indie" music scene caters to many niche and highbrow interests in much the same fashion that the "indie" film scene does for films. Typically indie music producers will release their work under less restrictive licensing; some have even gone so far as to survive on donations. See also: Creative Commons, Public Domain

Latency

The time lag between the initiation of an event and the completion of it. In audio, this is the time period transpiring between a digital and an analog signal. This applies both to the time it takes for the machine to turn microphone input into a digital record, and the time it takes to read in the digital data and output it as an audio signal to the speaker.

Leech

To download a file without providing the reciprocal upload. In file-sharing, it is considered bad form to continue to leech when there's only a few seeders. See also: BitTorrent, Seed

Lossless

Refers to any form of file compression in which no data is lost. Any codec using lossless compression will be guaranteed to reproduce the exact original quality no matter how many times the file is re-saved and transmitted. See also: Lossy

Lossy

Refers to any form of file compression which sacrifices the integrity of data in the name of tighter compression. Typically, this means that the data has places where "close enough" is acceptable. An easy analogy is made with image compression: The .jpeg file format may produce results with blurred, off-color, or aliased results, but arguably without it digital photography wouldn't have taken off yet, since perfect file records of high resolution photographs would take up so much memory space. See also: Lossless

MIDI

(Musical Instrument Digital Interface) An electronic protocol widely adopted for synthesized music. It should be noted that the MIDI format is not recorded or "played", specifically. Instead, it is composed directly on digital equipment, and when listened to, is merely a series of commands sent to a speaker or sound card to produce tones.

Mixer

A software program used to combine or control audio output. Sound mixing is a fact of all digital audio output. For instance, if you watch an action sequence in a movie with a car exploding while the background music is playing, without mixing you would hear the music stop while the explosion occurs. Mixing is to audio what multitasking is to computing.

MP3 (MPEG-1 Audio Layer 3)

The most popular and widely deployed audio file format for consumer audio storage and digital audio players in general. MP3 uses lossy compression, sacrificing higher-range frequencies for a highly compressed storage size. MP3 is such a widely accepted standard that a music player is likely to be called an "MP3 player" even when it plays other file formats. See also: AAC, FLAC, Helix

P2P (Peer-to-Peer)

The method of file transfer in which one end user may enter data transmission with another end user, without uploading the file to a third party. First-generation file-sharers had to go through a server, second-generation file-sharers were an attempt at decentralized file-sharing without a central index server, third-generation file-sharers introduced the concept of anonymous peer-to-peer file-sharing, and the fourth-generation gave us the "swarm" model of streaming peer-to-peer file-sharing that we have today.

Playlist

A list of audio tracks kept together, intended to be listened to as a group. Audio music consumers frequently keep several playlists for different occasions, and the sharing of playlists has become a social media activity.

PlaysForSure

Initially a form of content certification designed by Microsoft to indicate a device or program which would work with Microsoft-branded music files and vice-versa. Now a bitterly ironic name considering that it was revealed to be yet another form of DRM access management, and with the revelation that since PlaysForSure would be discontinued, PlaysForSure files would not work with subsequent media players, including Microsoft's own Zune. See also: DRM

Plug-In

Any software which is offered as an add-on feature for a larger software product. Frequently plug-ins are produced by third parties.

Power Adapter

The hardware which allows a device to be plugged directly into household current to obtain power, as opposed to running off a battery.

Public Domain

A creative work which is not restricted by copyright, either by the expiration of said copyright under copyright law or by intentional release of the work by the artist. Public domain works by definition belong to the public, and can be used for any purpose, including for profit. EBooks available through Project Gutenberg, the complete works of William Shakespeare, astronomy images from NASA, the song "Amazing Grace", and the fictional characters Tarzan and Dracula are all examples of creative works in the public domain. See also: Copyright, Creative Commons

RIAA (Recording Industry Association of America)

A commercial group which represents or claims to represent the recording industry in the United States. They are formed from a number of corporations including recording companies and publishers. The RIAA has made a highly famous name for itself in prosecuting any and all file-sharers they can find, although frequently these charges are dropped or thrown out after being shown to have been without merit. See also: ASCAP, BMI

Ringtone

A sound file played by a mobile phone device to indicate an incoming call. The mobile phone and mobile device age have spawned a cottage industry in ringtones, with users creating, uploading, downloading, and sharing ringtones across the mobile networks. Typically, the first thing a new user of a mobile phone does is set up the ringtone, and some users change theirs daily.

Rip

To extract audio file data from an audio CD, typically to a computer or mobile device. A software program which does this task is called a "ripper".

Rootkit

A malicious program which hides on a computer or other digital device, used to allow access to that device by a third party. Sony BMG music made a very famous name for themselves in 2005 by including rootkit software on music CDs that, in an attempt to enforce DRM, compromised the security of the infected device. The huge legal scandal that resulted led to rootkits becoming a cited example of just one of the things wrong with DRM. See also: DRM

Sample Rate

The resolution of a digitally stored audio file. In converting between analog and digital data, the digital side is stored and retrieved as a series of samples, just as an image file is stored as a series of pixels. Playing a sound back at a different sample rate from the one it was recorded at will result in a different, sometimes mangled, playback.

Seed

To provide a file for upload to a peer-to-peer file-sharing system, such as BitTorrent. It is considered good form to seed a file for at least as long as it took you to download it. See also: BitTorrent, Leech

Streaming Audio

The current preferred method of listening to audio files. In streaming audio, one may start hearing a file before it has finished downloading to one's device, as opposed to downloading it separately and then opening it to listen to it. See also: Flash

Throttling

To limit the rate at which one may upload and download data over a network connection. Some Internet service providers worldwide have recently taken to throttling customer's access speeds when they are suspected of file-sharing, regardless of the fact that the customer is paying for an all-purpose Internet connection.

Transcoding

To convert data from one codec or file format to another. Typically this is done with specialized software. This is often necessary thanks to the vast menagerie of codecs and file formats across the electronic world. See also: Codec

USB (Universal Serial Bus)

The standard method of connecting electronic devices and peripherals. Nearly every device and peripheral has standardized on using USB connectivity, as it is suited to both transmit a data signal and power in the same port.

VBR (Variable Bit rate)

A rate of encoding an audio sample in which the capture rate varies from place to place within the file. This allows for parts of an audio file which require less data to store, such as silence, to use less memory space. See also: CBR

Vorbis (also known as "Ogg Vorbis")

A free and open source audio codec, provided by the Xiph.Org Foundation as an alternative to the MP3 format. Like MP3, Vorbis is a lossy compression format. Vorbis has only partial support across hardware and software. In some cases, one may download a plug-in to support it in software.

WAV (Waveform Audio Format)

An audio codec format originated by Microsoft and IBM. Since it is typically an uncompressed format, its use is reserved for short sound effects and ringtones, as opposed to full-length music files.

WMA

(Windows Media Audio) An audio codec format designed by Microsoft. It is a proprietary format which is available in both lossy and lossless forms, intended for digital storage of music files. Widely deployed and supported across the Microsoft platform.