Version Numbering - NinjaCheetah/VisualBasic-Collection-Vol.1 GitHub Wiki
Here's how I mark versions:
vX - Larger versions are large updates, usually including new programs
vX.X - Smaller versions are small updates, usually with bugfixes and additions to existing programs
vX.Xb - "b", "c" etc. updates are the smallest, and only available by building the program yourself. They are tiny things like fixing an incorrect version number, or bugs that don't impact usage at all