In a world full of uncertainties, there are just two sure things left on the internet these days - sex and gambling. Sex has been done to death with recent stories of out of work dot.commers turning to porn websites to bring home the bacon, and Yahoo's big porn dilemma. But gambling, in particular the entertainment side of gambling - casinos - is just starting to emerge as a mainstream internet pastime. It has been held back, however, by the struggle for respectability.

Casino behemoth Aspinalls, which launches Aspinalls.com today, has put all its chips on its family name making it stand head and shoulders above the thousands of cowboy casino websites out there.

Its emphasis is on trust, says Russell Foreman, chief executive of Aspinalls Online. "It's all about making people feel comfortable. There's no way we'd do anything to jeopardise our reputation," he explains. The fact that Aspinalls.com is also the first publicly traded online gambling organisation in the UK, and thus has City shareholders to answer to, means that it is not going to do anything that might turn the public against it.

Foreman expects rapid growth for the business and says it's the perfect time to launch a big online casino, because internet consumers want entertainment, and websites want to start making money. With the web evolving to become an entertainment medium, the challenging gaming factor of casinos is guaranteed to pull in punters - even if they haven't got the nerve to play for money.

The games on offer are carbon copies of those found in ordinary casinos, such as blackjack, poker, roulette and craps. Croupiers are replaced by clever software that generates the numbers randomly. The more accountable online casinos make a big effort to ensure that these systems are subject to stringent control systems. Aspinalls.com, for instance, is to be audited regularly by PriceWaterhouseCoopers.

Many casinos ask players to download software onto their computers for faster and better play and set up accounts with credit cards, although most allow punters to play for free first to get the hang of the games.

But with so many casinos on the web, it's difficult to determine which ones are honest and which are out to rip off consumers. Gaming bodies suggest punters stick with well-known names, such as Ladbrokes (ladbrokescasino.com) and Victor Chandler (thespinroom.com), rather than the lesser known ones that don't offer guarantees of audits.

Now that more and more transparent casinos are launching online, it is forecast that this market segment will represent a major area of growth, particularly when the inevitable happens and they are granted UK licences.

New research bears this out. Peter Tyson, an analyst at Datamonitor, expects online casinos to grow at a much faster pace than any other subset of the online gambling market. "We're projecting a 40% growth rate for online casinos over the next five years, compared to just 20% for online sports betting," says Tyson.

Datamonitor says the UK online casino market accounts for around 40%, or almost £300m, of the online gambling market. By 2004, this is expected to have grown to 50% of the market, or £760m.

So it is no wonder that suddenly a whole batch of online casinos is cropping up. No sooner had Aspinalls starting publicising Aspinalls.com than MSN sent out a press release about its very own casino, provided by Harrods. The combination of Bill Gates and Mohamed Al Fayed cosying up together may be too much for most people to stomach, but nonetheless it's another key deal that will do wonders for the widespread acceptance of online casinos.

MSN, the world's most popular portal, is hoping to ease some of its revenue problems by offering a link to the Harrods Casino. It will pick up 10% of all gambling revenues referred to Harrods by MSN links and marketing. Sources within the online casino industry also suggest that Freeserve has for some time been looking at putting together a similar deal with a reputable casino operator.

In little more than six months, Harrods has established itself as one of the best-known online casino businesses, and the strategic two-year marketing deal with MSN, which kicks in later this month, can only serve to bring in more punters.

The Harrods Casino, a joint venture between the department store and Gaming Internet, is already proving to be Gaming Internet's principal revenue generator, according to a spokesman. Figures should be out soon, but early end-of-year analyst projections suggest that the casino should have generated £7.5m by this September.

Gaming Internet is one of a handful of technology companies that supply ready-made online casino systems to famous brands. Other big suppliers include Microgaming, Cryptologic and Boss Media, which are starting to make headway in the UK now that more and more traditional brands want to get involved. Gaming Internet already runs an online casino for FHM.com and is developing a casino for the Paris Ritz Hotel called ParisRitzCasino.com.

Given the ease with which companies can launch an online casino, it's no wonder that there is a glut of casino websites. But as more and more reputable companies get involved and take the lion's share of punters, the number of fraudulent websites should, in theory, dwindle.

"People are very concerned by how easy it is for companies they have never heard of to set up an online casino, and then rip them off," says Mark Brechin, author of a soon-to-be-released Mintel report on online gambling. "That's why the brand is absolutely vital and why reputable brands have to operate transparent and audited casino websites.

"Aspinalls' launch should do well thanks to the respect its brand has established over the past 40 years. However, there are still loads of shady sites out there ready to relieve the unwitting punters of their folding money," adds Brechin.

The reason "brand" is so important is that there is no real protection for consumers. The legalities of online casinos are sketchy, with most companies locating their servers and businesses overseas to circumvent antiquated gambling laws. Laws are gradually changing, however. The casino operators want the UK gam ing laws to be extended to protect consumers, and the government is thought likely to publish recommendations that should regulate online casinos and make them legal. Pundits are expecting the government, which loosened up the online gambling tax laws in the March 2001 budget, to clarify the antiquated online casino rules that are so prohibitive.

The most radical reform should be a single regulatory body set up to oversee the whole industry, effectively pooling the powers of the Gaming Board, the national lottery commission, the Jockey Club, the British Horseracing Board and the financial services authority.

The Gaming Board, the current regulatory body responsible for online casinos, is calling for a change in the regulations permitting online casinos in the UK. The reason companies go to the Caribbean, Central America and Gibraltar is that the governments of these territories are only too happy to grant licences in exchange for £100,000 for the licence and then tax on the turnover of the company.

Another key reform is expected to be the change in licensing laws, so that operators can be granted licences by a UK authority and don't have to purchase an offshore licence, or locate their servers abroad.

It's not difficult to work out how online casinos make money. Once people are hooked on the games, and they realise how easy it is to play, they become regular players. Loyalty systems are a big feature of online gambling and the theory is that regular gamblers can be easily be persuaded to use their accounts to have a punt on sporting events.

The next step, casino games on interactive television and on mobile phones tied into betting, is the final piece of the jigsaw for big casino players such as Aspinalls, turning us all into armchair roulette wheel addicts.