G'day Nayeem-monk,

"hmm I'm guessing ultimately Perl 5.38 and 5.0 both would exist for different purposes."

I think you may have misunderstood something here; or perhaps just made a false assumption. Perl version numbers have increased as new updates have been released: they're all versions of Perl; they do not have "different purposes".

Note the chronological progression of version numbers in perlhist.

The URL "https://metacpan.org/pod/perl" will show you the current stable version (5.36.0 at the time of writing). In the lefthand panel, the "Jump to version" dropdown list has links for versions going back to very early Perl5 versions.

Given a version like 5.x.y, development releases have an odd "x" number and stable releases have an even "x" number. This convention started around 5.6.0.

See also: "use VERSION"; "perldata: Version Strings"; "version (pragma)".