Summary

Are you confused with all the different version numbers? We have:

Software version

The version number of the software, as defined by the maintainer. Tends to be put on websites etc

Package version

The number of the package. Similar to RPM's Release number. Used only in the specfile. Used for "bugfix releases" of a package itself.

Interface version

Version number used to determine the interface compatibility of the software. + Major + Revision