System Administration Guide: Devices and File Systems

CD/DVD Media Commonly Used Terms

This section defines commonly used terms related to CD/DVD media.




CD read media that can be written once and after that, can only be read from. 


CD rewritable media that can be written to and erased. CD-RW media can only be read by CD-RW devices. 


Digital video disk (recordable) that can be written once and after that, can only be read from. These devices have much larger capacity than CD-R media. 


Digital video disk (recordable) that can be written once and after that, can only be read from. DVD+R devices have more complete error management system than DVD-R, which allows for more accurate burning to media, independent of the quality of the media. 


Digital video disk (rewritable) with storage capacity equal to a DVD-R. This media can be re-recorded by first erasing the entire disk. 


Digital video disk (random-access rewritable) with storage capacity equal to a DVD+R. This medium allows overwriting of individual blocks without erasing the entire disk. 


Digital video disk (random access memory, rewritable) with circular rather than spiral tracks and hard sectoring. 

ISO 9660 

ISO, an acronym for Industry Standards Organization, is an organization that sets standards for computer storage formats. 

An ISO 9660 file system is a standard CD or DVD file system that enables you to read the same CD or DVD on any major computer platform. The standard, issued in 1988, was written by an industry group named High Sierra, named after the High Sierra Hotel in Nevada. Almost all computers with CD or DVD drives can read files from an ISO 9660 file system. 

Joliet extensions 

Rock Ridge extensions 

Adds Windows file system information. 

Adds UNIX file system information. (Rock Ridge is named after the town in the movie Blazing Saddles.) 

Note –

These extensions are not exclusive. You can specify both mkisofs -R and -j options for compatibility with both systems. (See mkisofs(1M) for details.)

MMC-compliant recorder 

Acronym for Multi Media Command, which means these recorders comply with a common command set. Programs that can write to one MMC-compliant recorder should be able to write to all other recorders. 

Red Book CDDA 

Acronym for Compact Disc Digital Audio, which is an industry standard method for storing digital audio on compact discs. Also known by the term “Red Book” format. The official industry specification calls for one or more audio files sampled in 16-bit stereo sound at a sampling rate of 44.1 kilohertz (kHz). 

Commonly used terms when writing to CD media are:




The process of erasing data from the CD-RW media. 


The command to create ISO file system on a CD. 


A complete track with lead-in and lead-out information. 


A complete data or audio unit.