from perldata: 
Perl has three data structures: scalars, arrays of scalars, and associ
+ative arrays of scalars, known as ``hashes''. Normal arrays are index
+ed by number, starting with 0. (Negative subscripts count from the en
+d.) Hash arrays are indexed by string.

[download]
but actually reading perldata would be your best bet.

In reply to Re: What defines the choice of a Hash or an Array? by tcf03
in thread What defines the choice of a Hash or an Array? by ghenry

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