Guinness Stout celebrates its 250th anniversary on Thursday, and it's a remarkable achievement for the Irish brew.

It all began in 1752 when young Arthur Guinness inherited 100 pounds from his godfather, the Archbishop of Cashel, Dr. Arthur Price . The world has never been the same since.

Young Arthur's father had helped brew beer on the Archbishop's estate for the workers. Arthur and his brother decided to take their inheritance start a brewery in the town of Leixlip in County Kildare in 1756.

Three years later in 1759, the 34-year-old Arthur took a 9,000-year lease on a rundown brewery in St.J ames Gate, Dublin, and began brewing stout, a dark beer turned black by the roasting process. Not having any Madison Avenue advice on market positioning or brand identity, he simply named it Guinness.

That proved to be a wise move.

Today, Guinness is one of the world's most-popular drinks, and its 250th anniversary will be marked with a worldwide celebration: From Auckland to Austria and Dublin to Durban, the world will tip its hat and raise a pint to old Arthur and the legend he began.

At St.James Gate in Dublin, where the 9,000-year lease still has 8,750 years to go, the workers will still be brewing Guinness pretty much in the same fashion as Arthur did all those years ago. 

But now it is a worldwide phenomenon, one of the biggest-selling alcoholic drinks in Africa, a national treasure in Ireland where the Guinness storehouse is Ireland's leading tourist attraction, and exported all over the world wherever thirsty drinkers live.

How to pour the perfect pint of Guinness has been the subject of books, articles and many an argument at closing time. Experts say It should be poured three-quarters full, and then left to settle until the head (known as the Bishop's Collar because of its  foamy white appearance), settles on top. Then the pint is topped-up and served.

The entire process should take 119 seconds, according to the Guinness master brewers.  For many, it is well worth the wait -- the anticipation building as the seconds tick down to the top-up .With a flick of the wrist, a good barman can even imprint a shamrock symbol on the top of the pint.

The pint has been called a "porter," after the profession of the men who first drank it, 'the black stuff' and most memorably, the "pint of plain" by Irish writer Flann O'Brien who claimed '"a pint of plain is your only man'"to ease depression and woes. 

Its advertisements are legendary. "Guinness is Good For You" is one of the most-famous advertising slogans invented.  "My Goodness, my Guinnes"is another. Although the makers make no medical claims for the product, there are millions of Irish who firmly believe that the pick-me-up qualities of a pint of Guinness match anything the doctor can order.

Arthur Guinness himself was a retiring soul who would hardly understand the fuss. He was a strict Methodist who started the first Sunday Schools in Ireland . The family became widely known for creating good working conditions for its staff, including a free pint of the black stuff every day they worked.

No doubt, the thousands of Guinness workers will be downing their pint in celebration on the 250th anniversary.

Somewhere, Arthur must be smiling. Slainte (good health)! This one's for you, Arthur.