OS X version naming absurdity

Earlier this evening:

Claud… (6:08 PM):

i need mac OS X 10.4.8

josh.st (6:08 PM):

and have 10.4?

Claud… (6:08 PM):

no idea!

josh.st (6:09 PM):

leopard?

Claud… (6:09 PM):

no flippin idea

josh.st (6:10 PM):

panther?

josh.st (6:10 PM):

tiger

josh.st (6:10 PM):

?

josh.st (6:10 PM):

something with spots?

Claud… (6:10 PM):

OMGOSH!! STOP WITH THE ANIMALS! why!!

I had no answer why.