Unix encryption methods

[The Menagerie]

Can anyone out there tell me how passwords are encoded on Unix? (4.2BSD
at least, although if it is different on others, I'd be interested to
see other algorithms) Please note that I am *NOT* trying to break the
encryption, I just want to know specifically how it is done, so please
don't flame at me about the possibility/impossibility of breaking it. 

Thanks in advance.
					greg

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