The main difference between a hash and an array is that an array is indexed by number while a hash is indexed by name. So where a lookup in an array is fast if you know the position of the value, a lookup in a hash is fast if you know the "name" of the value, that is, the (string) key the value is associated with.

In reply to Re^3: Speeding up perl script by Corion
in thread Speeding up perl script by samuelalfred

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