Q. People down at the golf club have been talking about this thing called "the millennium". What is it, when's it on and where can I buy a ticket?
A. As everyone knows, the "Millennium" is a song by Robbie Williams. But there's also the mere detail of it being the biggest celebration ever staged on planet earth. Contrary to what champagne salesmen may be telling you, it doesn't actually begin until 2001 and this is because an Italian monk, Dionysus Exiguus, who introduced the notion of AD and BC, dated Christ's birth as AD1. Thus, the calendar goes from 1BC to AD1 with no year zero in between, making the two thousandth anniversary as the year 2001.
However the majority of people have overruled this scientific fact and decided to celebrate the millennium at the end of this year - even though the only significance the date has is that it's a big, round number.
This argument over where centuries begin and end has been going on since the first calendar was drawn up. On December 31st, 1799, the Times of London thundered in an editorial: "The present century will not terminate until 1 January 1801. We shall not pursue this matter further. It is a silly, churlish, childish discussion and only exposes the wants of brains of those who maintain a contrary opinion to that we have stated." So there.
Even those venerable keepers of time the Old Royal Observatory at Greenwich have gone on record as saying that while, strictly speaking, the new millennium doesn't start until 2001, they plan to celebrate it like every other sane person in 2000.
And as the year progresses, the "it's really 2001" brigade will become as irritating and irksome as the people who keep reminding you that Humphrey Bogart never actually said the words "Play it again, Sam" in Casablanca. If you insist on being pedantic, at least do it in style. A perfectly acceptable party conversation line is that the millennium has already happened: it took place back in 1996 (probably during the ad break for Kenny Live).
This is because of the confusion surrounding Jesus's actual birthdate - most academics accept that if Christ was indeed born during the rule of Herod, then his birth must have been in 4BC or earlier.
Best though to just chill out and go with the flow - the millennium begins at the end of this year.