At 01:32 PM 5/9/02 +1000, you wrote:
>If you aren't sure what a Hash (also called a message digest) is, it is
>basically a way to take the contents of a message and compute a unique
>(large) number. The idea is that no two messages will give you the same
>number and you can not recover the message from the number. They are often
>used to verify that the contents of a message have not been altered. Almost
>like a CRC.. but MUCH bigger and better. Look for "SHA" (sometimes called
>"SHS") and "MD5". These are the most common. I used SHA. SHA generates a 160
>bit number, MD5 a 128 bit number.

Hi Ash,

I don't think you really mean unique, do you? If the number is shorter than
the message then there MUST be more than one message that gives you the
same number.

Sean

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