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Chip's CD Media Resource Center:
CD-R (Recordable) 1

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CD-R (Recordable)

CD-Rs are occasionally still called WORM (write once, read multiple or many) devices, a generic designation that lacks marketing cachet, or as CD-WO, as they were originally dubbed by Philips and Sony. But the term "CD-R" has taken over when referring to the specific dye-layer based technology that we will discuss here, and is now in common use.

CD-R Standards

The CD-R specification is published by Philips and Sony in the Orange Book, available from Philips. I believe it was first published in 1988. The Orange Book now consists of several parts, and the latest editions have even abandoned the use of the term "CD-WO" in favor of "CD-R".

"Orange Book Part I" refers to CD-MO, a magneto-optical technology which I won't be discussing, and does not appear to be available from Philips at this time.

Regrettably, I don't have a copy of any of the Orange Book documents, and their content does not seem to be mirrored in publicly available standards. Therefore I've had to rely on secondary sources for all information related to the physical media.

CD-R Compatibility Requirements

Perhaps the most important objective in developing the CD-R technology was that the recorded discs be Red Book or Yellow Book compatible so they could be used with conventional CD players and CD-ROM drives. The developers' success in meeting this objective ranks as a huge accomplishment in that it suddenly, and for the first time, puts one of the fundamental tools of publishing in the hands of just about anybody, and at very little expense. In this it potentially far exceeds the impact of the Xerox copier.

A necessary corollary to physical compatibility is that the logical structure of a CD-R be identical to that used with CD-DA and CD-ROM. And in fact it is. But CD-Rs (and CD-RWs) also support an extended "non-sequential" volume and file structure. We'll discuss this in the section below on CD-R Volume and File Structure.


Last Updated Monday October 15, 2001 17:58:21 PDT