International Standard Recording Code, or ISO 3901 as its formal name is, is the recording industries answer to ISBN. Every recording, re-recording, remix and remastering is assigned a unique ISRC of their own. As an example of one of ISRC's uses the ISRC code is encoded in the Q-channel on every CD, right next to the actual recording.
The ISRC itself is 12 character long and contains information about where and when the recording was made and who owns it. The only characters allowed is 0-9 and A-Z. The ISRC is constructed in the following way:
|2||Country according to the ISO 3166 country codes.|
|3||First owner. An alfanumerical value unique for every record company|
|2||Last two digits of the year of the recording.|
|5||Designation code. A numerical value assigned by the 'first owner'.|