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

Teamnokaoi, your comments are counter-revolutionary. Loyal revolutionary guard forces would shortly be arriving at your home to take you and your family away to a "re-education camp", except that our money is worthless, and we can't even pay them with food, since our fearless leaders have consumed it all. Long live the revolution (yeah, right,...until the next tyrannical despot in the line of murderous succession!)

Zoya and Elizabeth.....thanks for the info from a neophyte. And Fatparrot...you missed "or it could be a woman's magazine"....you also missed your calling at the Comedy Club....thanks for the comedy relief!

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

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.

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