[ih] .UK vs .GB

[John Levine]

In another list someone was wondering why British domain names are
mostly in .UK even though the ISO 3166 code has always been .GB.

I know this came up before but can't find the discussion.  Pointers or
rehash welcome.  The first mention I can find of .UK is in an example
in RFC 821 in 1982, the first statement that ccTLDS would be ISO 3166
codes was in 1984.

For that matter, I see that JANET still runs .GB.  What still uses it?

R's,
John