An ISRC (International Standard Recording Code) is a unique 12-character alphanumeric code assigned to a sound recording. If a song has more than one recording, such as live, acoustic, or cover versions, each recording will have its own ISRC. Music services, publishers, and collection societies use ISRCs to identify and track specific sound recordings and match them to their underlying compositions. Typically, labels or distributors will assign ISRCs to recordings. An example of an ISRC is USS1Z followed by a number.