It's from the "old" days when there were many different email networks. The ".internet#" parts tells how to route to different gateways/networks. See http://ww

It's from the "old" days when there were many different email networks. The ".internet#" parts tells how to route to different gateways/networks. See http://www.faqs.org/faqs/mail/inter-network-guide/ http://www.faqs.org/faqs/mail/inter-network-guide/