I think you mean CC BY 4.0. There's CC0, CC BY, CC BY-SA, CC-BY-NC, or other combinations of below: BY: attribution SA: share-alike NC: non-commercial

I think you mean CC BY 4.0. There's CC0, CC BY, CC BY-SA, CC-BY-NC, or other combinations of below: BY: attribution SA: share-alike NC: non-commercial ND: no derivatives The "0" in CC0 just means no rights reserved. "4.0" is just the latest version of the legal code. There was a CC BY 3.0 and a CC BY 2.0, etc.