Glossary of Terms

Often a source of confusion is the .cda file.  On a windows computer, when you insert a RedBook Audio CD, the tracks show up as .cda files.  One might assume that these are the audio files on the disc because they are the only items that show up in the explorer window. . . that would be wrong.  The .cda files are merely placeholders pointing to a place on the CD that the song starts.  Think of them as what windows calls a 'shortcut'.

Jitter is a time-based signal error.  Often misunderstood, this problem can range from subtle and nearly inaudible to loud and distracting.  Jitter can reduce low-level resolution (add noise) and add distortion.What are they talking about when they say "Jitter"? Well, it can be several things.  This is part of the reason people are often confused with the topic.  Jitter can be induced by a poorly designed clock (the part of the digital device that sets the sample frequency. . .

Blue Book is the name given to the Enhanced Music CD or CD-Plus (a dual session yellow/red books) format. Its name comes from the series of books, also called the 'Rainbow Books' that define all compact disc formats. The first session on the disc is a red book session and can be played on any CD player. The second session is a yellowbook session. This can be any data readable by a computer. There is almost no limit to what you can add to you audio CD release.
Yellow Book is the name given to the data compact disc (a common CD-ROM) format. Its name comes from the series of books, also called the 'Rainbow Books' that define all compact disc formats. It was developed by the creator of the compact disc, Sony/Phillips, and is now one of the most common CD formats.
Often confused with CD-Text, the online Compact Disc Database stores metadata on audio CD's.  The online database was created by Gracenote and is accessed by client applications, such as iTunes.  The client application sends a 'disc thumbprint' then the information in the database is downloaded and displayed in the program.  Sometimes, especially with burned discs, there are multiple entries in the database for that thumb print due to several users adding their personal 'mix cds' to the database.

CD-Text extends the Red Book specification and allows metadata to be embedded into the physical disc.  The information about album artist, album title, track title, track artist, ISRC, arranger, composer, performer, songwriter, and a message can all be are stored either in the disc's table of contents (TOC) or in the subchannels R through W.  Only disc players with the special compact disc digital audio cd-text logo will read and output this data.  Most computers use another method of getting cd metadata called the CD Database (CDDB).


Also known as a 'bar code,' the Universal Product Code consists of a series of black and white lines that contain information decodable by an optical scanner. The pattern represents 12 numeric digits that help retail stores manage inventory and sell items. This information can also be digitally embedded into your disc at mastering.

International Standard Recording Code permanently and uniquely identifies sound recordings.
PQ codes are the first 2 of 8 sub-channel information encoded on a 'Red Book' CD.

Red Book is the name given to the compact disc digital audio format.