I have no idea. UUCP (Usenet) addresses used to be (are?) "backwards" and ! sepa...

		s3graham on Oct 17, 2009 \| parent \| context \| favorite \| on: Ask HN: why are domain names reversely ordered? I have no idea. UUCP (Usenet) addresses used to be (are?) "backwards" and ! separated. Maybe some historical references related to that would point you to more info. If I were to guess though, I'd guess email addresses. me@machine being originally valid makes me@tld.machine harder to parse?

They weren't really addresses; it was a series of hosts. It was thus more like a route.