Pardon my naivete, but what does "redbook" mean?

REDBOOK CD SPECKs
This should help. Only recently I have learned it myself. Welcome and good luck.

The original group that developed the compact disc (Sony and Phillips) had a variety of rule sets for different types of compact disc creation, use, and specifications.
The part of the compact disc specifications for commercial prerecorded compact discs was call the "Red book". Others were Orange book, etc.
The Red Book specifications are the basis for all the commercial CDs and commercial CD players on the market.
(Some of the anti-copy things violate the "redbook" rules)
So to say "Redbook" means complying with the "gold standard" of compact disc creation and playback.

Or it could mean...
A pricing guide for numismatists (coin collectors)
A communist revolutionary's handbook