One addition to the preceding good advice. If you find yourself having to re-sort the same(sup>1*) hash more than once in your code, a useful optimisation is to keep an array that contains the keys in their sorted order and use that the second and subsequent times.

my %hash = ( your => 1, data => 2, goes = 3, here => 4 );
my @sorted_keys = sort keys %hash;

for( @sort_keys ) {
    print $hash{ $_ };
}
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¹ If you only change the values, ten you can re-use @sorted_keys ok, but if you add or delete keys to/from %hash, then @sorted_keys would need to be regenerated. This is only of real benefit if

• Your keys never change.
• Your hash is very large.

For small hashes, or those where the keys are constantly changing, or if your only iterating the hash once, this idea is best forgotten :)