Here's an excellent article by xdg that will help clear things up: version-numbers-should-be-boring.

Update: I just noticed where your confusion might be originating

our $VERSION = '0.08';
$Version = eval $VERSION;
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"0.08' doesn't fit in here. Using xdg's example:

our $VERSION = '0.001_001';
$VERSION = eval $VERSION;
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It's the "decimal alpha version" or the numbers used by "developer releases". Those releases must use decimal alpha to keep from reporting the wrong module version number.