This is increasingly less tru as TLD's like .amazon are being given out. There's no reason that a or b in format a.b is more important, other than the fact tha

This is increasingly less tru as TLD's like .amazon are being given out. There's no reason that a or b in format a.b is more important, other than the fact that the arbitrary convention exists that a can be anything but b can only be one of a few choices.