# hash of hashes # hash - curly brackets $hashref1 = {key1 => value1, key2 => value2, key3 => value3, key4 => value4}; $hashref2 = {key1 => value1, key2 => value2, key3 => value3, key4 => value4}; $hashref3 = {key1 => value1, key2 => value2, key3 => value3, key4 => value4}; # hash of hashes, which brackets? :) $hash_of_hashes = {key11 => $hashref1, key22 => $hashref2, key33 => $hashref3}; # see how it looks: use Data::Dumper; print Dumper $hash_of_hashes; # get an element. Nothing surprising, starting from 'outer' level: $$hash_of_hashes{key22}......... # and end with 'inner' key $$hash_of_hashes{key22}{key4};