Magie sold The Landlord's Game to toy and game giant Parker Brothers in 1935; by then Parker had already started selling Monopoly - but it was clearly influenced by The Landlord's Game. As part of the deal, the company continued to make The Landlord's Game until 1939, but it was massively outsold by its own offspring.

A board that even more closely resembles the current game was introduced in the 1930s, based on Atlantic City, New Jersey, and it quickly became the most popular board game in the US. "Many feel that it gained popularity because people were looking for an escape from the financial hardships they were feeling and it offered the fantasy of being rich," says a spokeswoman for toy company Hasbro, which took control of Monopoly when it absorbed Parker.

The game quickly spread to Britain and then throughout the world, with licensees producing localised versions of the board. By the second world war it had become so popular that the British Secret Service was using front organisations to distribute the game to Allied prisoners of war except these versions were filled with maps, compasses, money and other equipment that could help them to escape.

The variants, formats and game extensions have mushroomed in the past couple of decades: as well as endless local editions, there are versions with cities instead of individual properties; with a bigger board featuring more properties; with electronic money replacing paper; and with contemporary locations and prices.

There are even editions based around and , and there are card games, video games and even slot machines.

Perhaps the biggest reason for the game's success is its popularity with players of all ages. Children, in particular, like it because it gives them a chance to handle money and make adult investment decisions, practising skills of investment and negotiation that are critical in adult life, but with no danger of real loss.

"One of the reasons Monopoly has endured for generations is that it offers a classic gameplay that appeals to kids, parents and grandparents alike," the Hasbro spokeswoman says. "It allows players to live the fantasy of buying and selling property."

In Hong Kong, of course, that's a common fantasy. A game about property with a strong appeal to gamblers' instincts, it's hardly surprising Monopoly has long been a hit in the city. The original Hong Kong edition was introduced in the 1960s, and has been updated with new versions and properties in both Chinese and English since, although Classic Hong Kong Monopoly remains the most popular.

There are also three versions on the mainland, including a 2008 Beijing edition released to coincide with the Olympics.

According to Patrick Chugh, the founder and one of the organisers of the Hong Kong Board Gamers Club, a 1,400-strong group whose members meet in small groups once or twice a week in cafes to play board games, Monopoly is still the most requested game at the club.

"Whenever I talk about board games, the first game people mention is Monopoly," he says.

"It's a great game. It teaches you about life - there's a philosophical aspect to it. It's about people competing for limited resources. It trains people to take risks, but also to plan - you have to make sure you have money saved up in case you go to jail. People go through the same emotions playing it as if these things had really happened to them. You can tell what people are like by the way they play the game."

So eminent is Hong Kong in the Monopoly world, in fact, that the city even boasts a former Monopoly world champion.

There have been 13 Monopoly World Championships, organised by Hasbro, since 1973, held across the US and in places as diverse as Bermuda, Monte Carlo and Tokyo. It's even been on ESPN.

Winners have come from the US, Singapore, Japan, Britain, Ireland, Italy, Norway, the Netherlands, Spain - and, in 1996, Hong Kong, in the form of author, teacher and Monopoly fanatic Christopher Ng Hon-yuen, who writes children's fiction under the pen name of Chairman Butt.

Introduced to the game as a child by his sister, Ng became more serious about playing it as he got older; he entered local contests and was twice Hong Kong champion. In 1996, the World Championship organisers wanted to broaden the focus of the contest away from the US, and invited the champions of 34 countries to compete. Ng won a local competition featuring more than 120 participants in June, and by September was off to Monte Carlo for the World Championship.

The tournament started with a preliminary round, in which each of the 34 competitors took part in four games, with the top five cumulative prize-winners progressing to the final. Ng qualified in fifth - and went on to win the final.

His prize: a Monopoly set with real money. But Ng thinks he might have won some people quite a lot of money, too; this being Monte Carlo, there was a fair amount of side-betting among the audience.

"It was fun," he recalls. "The atmosphere was kind of leisurely, the people were very friendly". He also made a lot of friends there, people with whom he kept in touch afterwards. "When I went to defend my title in Toronto in 2000, though, the atmosphere had changed: everyone was a lot more serious.

"I was glad to win for Hong Kong, because Hong Kong is a leader in finance and property trading."

Winning at Monopoly is more complex than it seems. Some tactics are obvious, however, because some groups of properties offer a better return on investment. There are four railway stations, for example, meaning each player has a good chance of landing on one during a single trip around the board. The orange set are also a top buy, largely because several Chance and Community Chest cards send you there, as are the red set.

At the opposite end of the scale, the green set are just after the Go To Jail square and are expensive to develop; the same applies to a lesser extent to the dark blues next to them, the priciest properties of all; and there are only two utilities, so they aren't landed on often.

Buying only a single property from a set is also a bad use of your limited resources. Like many of the best games, though, the optimum strategy often has little to do with the decisions you make and more with how you interact with other players.

Those interactions, and players' willingness to trade with each other, are one of the factors that determine another striking aspect of the game: its duration. Because Monopoly, as everyone who has played it knows, can go on a bit: the longest recorded game lasted 1,680 hours, the equivalent of 70 days without a break.

The "speed die", introduced in 2006, is a third die with faces featuring a bus and a Mr Monopoly (the game's mascot, formerly known by the somewhat creepy epithet Rich Uncle Pennybags), as well as three numbered faces, that makes the game go quicker by giving the roller more advantageous options.

Various rule modifications allow the game to be completed more quickly, including time limits, assigning properties to players randomly at the start, and finishing the game after two players go bankrupt. House rules like these, in fact, are a feature of Monopoly, and the ability of players to tinker with the rules without damaging the gameplay is a big reason for the game's success.

Another reason the game can last so long is that many people play it wrongly. When a player lands on a property and chooses not to buy it, the rules state that it is then put up for auction, at any price, to anyone - including the player who turned it down - but few people observe this, even though it makes the gameplay more subtle and sophisticated.

But however people play it, Monopoly's unique cultural position is assured. Its terminology has infiltrated mainstream English, from Get Out Of Jail Free cards to referring to worthless currency as Monopoly money. But not all Monopoly money is worthless: Ng won US$15,140 for his world championship title, while San Francisco jeweller Sidney Mobell produced a version with a 23-carat gold board and diamond-studded dice, worth US$2 million. Surely a similar Hong Kong edition can be only a matter of time.