What is it?Known simply as "The Open" in the land which hates to waste a word, and "The British Open" everywhere else.
And it's important?The British Open is the oldest of the four major championships - first played in 1860 - and, since Pádraig Harrington's victory last year, it's the most important and prestigious of the four as well, in our minds anyway.
Though it is the one that pays the least. For example, this year's champion will walk away with only €940,000. When Peter Thomson won in 1954, the first of the eight times Royal Birkdale has staged the event, he walked away with £750 (€940). And when the only other Irishman to win the competition, Fred Daly, claimed first place in 1947 at Royal Liverpool Golf Club, he took home £150 (€188).
So what do I need to know?Everyone outside the top 70 and ties, and outside 10 strokes of the leader, on Friday evening - presuming the weather holds up - will have the weekend off. Those of us who only ever have a good game when we're driving the fastest cart can sympathise.
Jean Van de Velde famously lost a three-shot lead at the final hole in the 1999 British Open at Carnoustie. Of course, the Frenchman should have known the Rules of golf insist that, during the final hole of every round, your score will annoyingly automatically adjust to what it should be.
So who'll win?With no Tiger Woods, we can't give you a definite answer. But the other usual suspects are there - including Sergio Garcia, Ernie Els, Lee Westwood, Phil Mickelson and, of course, the reigning champion, even if he has to play one-handed. Damien McGrane will begin this year's Irish challenge for honours at the ungodly hour of 7.03am tomorrow, with Harrington at the first tee less than an hour later.
Philip Walton - playing his first British Open in 10 years - and Graeme McDowell will start on the 7,173-yard, par-70 course either side of noon.
Darren Clarke won't be there, even though on Betfair yesterday you could still lay odds on him to win the title. Sounds like easy money, but it's a little risky betting €2,000 to win a tenner - no matter how sure you are of winning.
On TV?Setanta Ireland will be showing almost every single shot at the course beside the Mersey during the next four days.
And in keeping with the rule that all amateurs believe themselves worthy of judging the professional game - in fact the higher your handicap the more qualified you are to operate as an instructor - Gary Lineker is heading the BBC's coverage.
As ever, he'll be joined by a huge cast, which includes Peter Alliss, Ken Brown, Wayne Grady, Sam Torrance and Andrew Cotter.
