In additional to AnonMonks excellent explanation I'd like to point you to perlreftut, which introduces you to the sublteties of references in Perl 5.

Another good document is the Perl Data Structures Cookbook.

Perl 6 - links to (nearly) everything that is Perl 6.

In reply to Re^2: Returning multiple Hash references from a sub() by moritz
in thread Returning multiple Hash references from a sub() by Xhings

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