On Wed, Aug 06, 2008 at 10:24:16AM +0100, Nicholas D. Richards wrote:

The former. Sort of. The building I live in has three flats in it,
numbered 1, 2 and 3. Flats 2 and 3 share a common front door and
hallway, having their own doors off that. As far as normal people are
concerned, that's three flats and three addresses. Post for flats 2 and 3
is delivered through a single letterbox. Consequently, as far as the post
office is concerned, there are only *two* addresses, one for flat 1, and
one for the shared letterbox of flats 2 and 3.

This is quite irritating, especially when stupid programmers working for
stupid companies insist that I tell them my address by typing in my
postcode and then selecting one of the addresses that the post office
think exist. Normally it doesn't matter, of course, but it does matter
when I'm trying to do something like order a pizza late at night and
want the delivery boy to ring *my* doorbell and not have to guess at
random between mine and my upstairs neighbour's.