There are three pieces of information this site uses to identify different pressings of CDs. This page explains what that information is, why it is important, and how to locate it when you want to compare your CD with what is on the website. If you are submitting new waveform data, you’ll need to provide this info with your submission.
This is the ID that the record label assigns to the release. This will be used by many different pressings. If the catalog # is different, it’s very likely to be a re-release and will most likely have been remastered.
This is the next most specific identifier. Barcodes can be different between regions or record labels. There are many labels that will use a portion of the barcode as the catalog number.
This is the most specific identifier of a pressing, so it also the most valuable. This number is engraved in the CD itself, not just printed on the face of the CD or the jewel case. This number is found on the inner ring of the CD and provides information as to where the CD was manufactured.