Illustrated Guide to Hashes

<a href="http://unixwiz.net/techtips/iguide-crypto-
hashes.html">Here's Steve Friedl's An Illustrated Guide to
Cryptographic Hashes. He states that he wrote the article because
of the recent discovered weaknesses and to explain to the general public
what hashes are and what they're used for. Sort of a "the sky is not
falling, only a piece of it" article?