If you need to store more information, consider a more complex data structure. reptile suggests a hash of lists. I would choose a hash of hashes. 
my %data = (
    'US' => {
        Florida => 'Miami',
        Illinois => 'Chicago',
        New York => 'New York City' },
    'Canada' => {
        British Columbia => 'Alberta',
        Saskatchewan => 'Saskatoon',
        Ontario => 'Toronto' }
);

[download]
The appropriate perldoc pages are perldsc and perlref.

(Oh, a hash is an associative array. That means that it takes the first element -- New York, for example -- and runs it through a hashing algorithm to generate a unique index, which helps it locate the key -- New York City -- in an internal data structure. If the hashing algorithm is good, "New York" will always come up with the same hash value, which is why duplicate keys are not very useful.)

In reply to Re: Can a hash name have the same value twice. by chromatic
in thread Can a hash name have the same value twice. by DavidBer

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