Extended KotD #4, #5, and #6: _CRC32, _ADLER32, _MD5$

[SMcNeill]

"ABC" might have a value of 6, while "AAD" would also have that same value of 6.

if one method fails, would one of the other methods succeed?

Aye, as each are different algorithms for finding the checksum.  

And it's not so much that they "fail".  It's that the don't always guarantee UNIQUE results.

"Applesauce" might checksum to "AXYZ97".
At the same time, "Byttermilk" might also checksum to "AXYZ97".

Now, chances are, if I send "Applesauce" to you, it's not going to corrupt to the point where it becomes "Byttermilk".

If your checksum doesn't match mine, you 100% know something is wrong.  <<-- this is what you're using checksums to check for.  Not the rare "oh, this might match too", issue.

Think of it like car keys.  A million cars made each year, with maybe a thousand different keys between them.  Will your key open a car in every state?  Sure, it probably will!  But will it open your neighbor's car?  Wouldn't think so.