From Xojo Documentation
The major version of the ConsoleApplication, corresponding to the version information. The range is from 0 to 255. This can only be set in the IDE, but you can read the value in your code.
Typically version numbers are written as 188.8.131.52 (MajorVersion.MinorVersion.BugVersion.NonReleaseVersion).
Puts all the individual versions together to create the full version: