CD Spin  Words to Record By  CD Spin


Access Time
With hard disks or compact discs (CDs), maximum access time is the time it takes to move from one end of the disc to the other, find a piece of data and transfer that information to RAM.
Buffer
Memory that stores data to compensate for differences in the transfer rate of data from one device to another.
Cache
RAM used for temporary storage of data that must be accessed very quickly, typically used to store directory files.
Close Session
When a recording session is closed, information about its contents is written into the CDs Table of Contents. A lead-in is written to prepare the CD for a subsequent session.
Extension
 In the logical format of a disk or disc, a "branch" of the information tree containing other directories/sub-directories and/or files.
HFS
The file system used by the Macintosh.
High Sierra Format
The standard logical format for CD-ROM originally proposed by the High Sierra Group, on which the ISO 9660 standard is based; essentially identical to ISO 9660.
Hybrid
In popular use the term "hybrid" often refers to a disc containing both DOS/Windows and Macintosh software, in which a DOS/Windows platform sees ISO 9660 and the Macintosh sees HFS.
ISO 9660 Format
An international standard specifying the logical format for files and directories on a CD-ROM.
Logical Format
ISO 9660 translates the sector-by-sector view of a CD into a virtual "tree" of directories and files, which makes it easier for both humans and computers to use the information on the disc.
Mastering
Refers to the process of creating a glass master from which CDs will be reproduced in quantity. In CD-R systems, mastering is done together with pre-mastering by the desktop CD recorder, and the term mastering is used generally to mean "recording."
MSCDEX
MS-DOS extensions for CD-ROM, not needed for Windows 95 or 98. It allows DOS to recognize CD as a DOS volume.
Mixed-Mode Disc
A CD including both computer data and CD-DA tracks. The data is all contained in Track 1, and the audio (CD-DA) in one or more of the following tracks.
On-the-Fly
To write on-the-fly means to write to CD data referenced in a virtual image without first writing a real ISO 9660 image.
Orange Book
The Philips/Sony specification for Compact Disc Magneto-Optical (CD-MO) and Write-Once (CD-WO) systems.
Photo CD
A CD format based on the CD-ROM XA and Orange Book Hybrid Disc specifications, used to store photo-graphic images for display and printing.
Pre-Gap
A space dividing tracks, recorded before the track data area. The length of the pre-gap varies with the CD recorder and the types of tracks. Where successive tracks are both of data, one track is separated from another by a track pre-gap of 150 sectors (2 seconds). Where successive tracks are of different types, the pre-gap is usually 225 sectors (3 seconds). If two successive tracks are audio, there may be no pre-gap at all.
Pre-mastering
The process of preparing data to be recorded onto a CD. This includes breaking the data into sectors and recording those sectors with the appropriate header (address) and error correction information. In the case of recordable CD systems, pre-mastering and mastering are done in one operation, resulting in a ready to read CD.
Red Book
The Philips/Sony specification for audio (CD-DA) CDs.
Sector
The smallest recordable unit on a CD. A disc can contain 75 sectors/second X 60 seconds/minute X number of minutes on disc. The amount of data contained in the sector depends on the physical format and mode it's recorded in. For "regular" CD-ROM (Mode 1) data, you can fit 2048 bytes or 2K of data into a sector.
Volume Descriptors
Fixed-length records that contain vital information about the CD and how to read it.
Yellow Book
The book that sets the standard developed by Philips and Sony for the physical format of CDs to be used for information storage.

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Date of last revision: 17 December 2001
Extracted from: Imaging Magazine December 1997