"Redbook CD's" ??

All of a sudden I see the term "redbook CD" start popping up all over this and other sights. What is a Redbook CD?
Redundant, that's what. "Redbook" is the set of standards (there really was a red book) governing the CD format.
The regular old CD you have been using for years. This is in contrast to SACD and DVDA etc. so the term has become more popular since the advent of these new formats. I asked the same thing a while back! Arthur
Regular audio CDs. The 'red book' was where the specs were originally defined.
Radiohead's Amnesiac is a red book cd.