How are hash functions like MD5 unique?

Posted by Aly on Stack Overflow See other posts from Stack Overflow or by Aly
Published on 2010-03-14T23:44:08Z Indexed on 2010/03/15 0:09 UTC
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Im aware that MD5 has had some collisions but this is more of a high level question about hashing functions. If MD5 hashes any arbitrary string into a 32-digit hex value, then according to the Pigeonhole Principle surely this can not be unique as there are more unique arbitrary strings than there are unique 32-digit hex values

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