What is the difference between version and release of a DBMS?

New version of a software product means many changes and additional  many new features. But with new release there is typically minor changes, with fewer changes and new features.

For example: Moving from an oracle 11g to 12c is a version change and there would be major changes. However, moving from oracle 11g R1 to 11g R2 is  a release change and there would be a small number of changes.