If it will help you, a sample of Hash of Hashes: 
my %hash = ();
$hash{'jeep'}{'wrangler'} = 1;
$hash{'jeep'}{'liberty'} = 1;
$hash{'ford'}{'pinto'} = 1;
$hash{'ford'}{'taurus'} = 1;

[download]

You can use Data::Dumper to see what %hash looks like, and probably it will help you understand hash of hashes better.

In reply to Re: hash of hashes by marinersk
in thread hash of hashes by Anonymous Monk

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