GRid is a unique identifier for digital albums. GRid stands for Global Release Identifier, and it's part of a system that allows digital music files to be identified, constituting the electronic version of the UPC.
And why GRid in addition to the UPC?
Although UPC codes are effective when tracking physical sales of specific content, they are not as effective when it comes to songs that are sold digitally.
The GRid, consisting of a unique code assigned to each digitally distributed content, ensures that artists are rewarded for each digital sale made on the internet.
Even though, for now, it is NOT a mandatory requirement to distribute your music.
How can I get the GRid code?
GRid codes can be obtained from the official IFPI website, you can directly access the form by clicking here.