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A portion of RAM aside as a buffer between the CPU and either a hard disk or slower RAM. It used for temporary storage of data which must be accessed very quickly.  In applications which run from CD-ROMs, the cache is typically used to store directory files.

The plastic and metal carrier into which a CD must be inserted before it is loaded into some CD-ROM drives or CD recorders.

Common Access Method. The proposed ANSI software interface for SCSI devices and a part of SCSI-3 standard. A specification (API), developed by an industry committee, for a common structured method of supporting SCSI peripherals.

Cascading Drivers
Drivers that can connect to, and thereby work with, other drivers.

Commite Consultatif International de Telephones et Telegraphes. The old name for the ITU-T.

See Common Command Set.

See Compact Disc.

CD Audio
Standard CD format for storing audio souindtracks. For example, music and songs.

See Command desciptor block.

CD Bridge
A set of specifications defining a way of recording CD-Iinformation on a CD-ROM disc.  Used for Photo CD and Video CD.

CD+Graphics. Audio, text and graphics used in the same application. This type of disc is usually used for Karaoke machines.

Compact Disc-Digital Audio. A CD-DA disc contains tracks with Audio sectors only.   Jointly developed by Philips and Sony and launched in October 1982, CD-DA was the first incarnation of the compact disc used to digitally record and play back music at unprecedented quality. The standard under which CD-DA discs are recorded is known as the Red Book.

A compact disc format designed to allow interactive multimedia applications to be played through a computer/disc player attached to a television. Especially good for real-time animation, video, and sound. The CD-I standard is called the Green Book.

Compact Disc Recordable. A special type of CD that can be written to one time.   It is primarily used for making a master disc to be mass-produced.

Compact disc-rewritable. The most recent addition to the compact disc family. It was originally called "CD-Erasable." The official name is CD-ReWritable, and it is a media and recording system that alows the user to erase previously recorded information and then record new information onto the same physical location on the disc.

Compact Disk-Read Only Memory. An optical storage technology that uses compact disks to distribute information in audio format (74 Minutes per disk), as computer data (up to 650 megabytes per disk), or a combination of audio and data formats.

CDs are a popular method of publishing and distributing large amounts of information such as databases, catalogs, graphics, software applications, and multi-media presentations.

Using optical laser technology to create CDs, a laser burns microscopic pits into a light-sensitive coating on a master disk. Copies made from the master disk are encased in clear, highly durable polycarbonate plastic.

To read a CD, a laser and lens measure the intensity of light reflected back from the surface of the disk. Light that strikes a microscopic pit is scattered, and very little returns to the lens. Light that strikes a flat portion of the disk is reflected straight into the lens.

A Photo Detector measures the strength of the light reflected through the lens and makes a current that's proportional to the intensity of light. The constantly changing current is interpreted as information.

"XA" stands for Extended Architecture, a bridge between Yellow Book and CD-i CD-ROM XA is an extension of the Yellow Book standard, generally consistent with the ISO 9660 logical format but designed to add better audio and video capabilities (taken from the CD-I standard) so that CD-ROM can more easily be used for multimedia applications. CD-ROM XA is also the physical format for Photo CD discs.

Mode 1
Standard Yellow Book sectors

Mode 2
May be of form-1 or form-2

Form 1
2048 bytes/ sector, with ECC (Error Correction) for data
Form 2
2328 bytes/ sector, without ECC, for audio/video

Compact Disc-Write Once. Recordable compact disc.

Centronics interface (cable)
See Parallel Interface.

A special international committee on radio interference (Committee, International and Special, for Protection in Radio).

Close Disc
To "close" a recordable disc so that no further data can be written to it. This is done when the last session's lead-in is written - the next writeable address is not recorded in that lead-in, so the CD recorder in subsequent attempts to write has no way of knowing where to begin writing. It is NOT necessary to close a disc in order to read it in a normal CD-ROM drive. 

Close Session
When a session is closed, information about its contents is written into the disc's Table of Contents, and a lead-in and lead-out are written to prepare the disc for a subsequent session.

A group of sectors on a disk. DOS allocates disk space to files in clusters.

Complementary Metal Oxide Semiconductor. A small section of RAM used to hold certain hardware configuration parameters in IBM and compatible computers.

Command Chaining
Combining multiple SCSI commands into a single group in order to reduce the overhead of many  individual commands.

Command Descriptor Block(CDB)
A block of SCSI information containing the command, parameter, and address information needed by the target to carry out a certain task.

Command Queuing
In SCSI-1, initiators were limited to one command per LUN e.g. a disk drive. Now up to 256 commands can be outstanding to one LUN. The target is allowed to re-sequence the order of command execution to optimize seek motions. Queued commands require Tag messages, which follow the Identify.

Common Command Set(CCS)
A standard set of commands for communicating with SCSI devices.

Compact Disc
CD stands for compact disc which is a general term for all formats of CD media.   CD formats available on the market now include CD Audio, CD-ROM, CD-ROMXA, VideoCD, CD-I and others.

An optical disc capable of storing the equivalent of hundreds of floppy disks.   See CD-ROM

To translate source code written in a high-level language into object code.

COM Port
Also called a serial port. A connection on an IBM or compatible computer, usually named COM1, where you plug in the cable for a serial device. Common serial devices are printers and modems. Serial ports are smaller than parallel ports and usually contain 9 pins.

Refers to the way a computer is set up; the combined hardware components (computer, monitor, keyboard, and peripheral devices) that make up a computer system; or the software settings that allow the hardware components to communicate with each other.

Controller Card
A circuit board that plugs into the motherboard on the computer. Controller cards allow the computer to communicate and control devices. SCSI and IDE cards are examples of hard disk controller cards. Some printers and scanners also require controller cards, called printer controller cards and scanner controller cards, respectively.

Conventional Memory
In an IBM PC or compatible computer, up to the first 640K of memory in your computer. MS-DOS by default uses only this memory to run programs.

An additional processor chip which increases the computer's speed by handling specialized chores such as math or graphics.

Corel Corpration is a world leader in the development of graphics software and SCSI (Small Computer System Interface) software. Founded in June 1985 by Dr. Michael Cowpland, the company was engaged primarily in systems integration.  Corel provided customers with turnkey PC-based desktop publishing systems and local area networks by combining hardware and software products from various manufactures with the company's proprietary software enhancements.

Products available from Corel include CorelSCSI 2, Corel CD PowerPak, CorelSCSI Network Manager, CorelDRAW, Corel Professional Photos and Corel Ventura.

CorelSCSI supports SCSI devices such as:

-Host Adapters
-CD-ROM drives
-WORM drives
-Communications devices
-Hard Drives
-Rewritable drives
-Floptical drives
-Tape drives

Corel's Product Certification program tests new peripherals as they're introduced to the market, guaranteeing that, today and into the future, you can easily integrate virtually any SCSI peripheral into your systems. For a current list of Corel-Certified devices, call Corel's FAX Back number, (613) 728-0826, mailbox 3080, and ask for document 1009.

Central Processing Unit. The "brain" of the computer that performs the actual computations.  The term Micro Processor Unit (MPU) is also used. The main microprocessor in a computer. The CPU carries out the primary functions of the computer. The intel 80386, 80486, Pentium and  pentium II are examples of CPUs.

Cross-platform hardware or software can function on more than one type of computer(e.g. PC,  Macintosh, or Sun) or operating system (e.g., DOS, Windows, or UNIX).

Cross Section
An illustration that shows what something looks like after being cut.

Cross Talk
Interference between two wires caused by the signal from one wire appearing on the other.

Cue Sheet
In Easy-CD Pro for Windows 3.1, a list of tracks which will be written one after the other in the same session without user intervention. Generally used to create multi-track audio or mixed-mode discs.

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