Pirate software now accounts for more than a third of the programs installed on the world's computers, and last year cost the software industry $28bn (£15bn) in lost revenues. Or so says the Business Software Alliance, a consortium of leading software vendors, using numbers produced by International Data Corporation (IDC).

The US has the lowest incidence of pirate software, at 22%, while Vietnam and China had the highest, at 92%. The UK scored 29%, the same as Japan.

This does not mean UK users can relax. It's a safe bet that BSA members are much more concerned about piracy in the UK than they are in Ukraine, for example, which has a piracy rate of 91%. I can think of two good reasons why.

First, the UK is a much bigger market: software piracy in the UK cost $1.6bn, whereas in Ukraine, it only cost $92m. Second, BSA members stand a reasonable chance of making British companies pay up. They have very little chance of collecting much money in Ukraine, Zimbabwe, Nigeria, Pakistan and other poor countries.

And while third world piracy represents a "loss" for software suppliers, it does have benefits. Those illegal copies of, say, PhotoShop, are helping to develop millions of skilled PhotoShop users. Some of those people will eventually get jobs using the program, or start earning enough to want a legal, supported upgrade. In the long run, this is probably better for Adobe than driving them to a would-be rival.

But BSA members could also do more to make their products affordable in less-developed countries. Last year in Thailand, for example, Microsoft supplied restricted, localised versions of Windows XP and Office for 1,490 baht (£20) as part of a government-backed PC project. "Normal" prices would have been 4,500 baht (£59) for XP Home and 15,000 baht (£198) for Office XP. This year, Malaysia did a similar deal.

Last week, the Motion Picture Association of America also released a study of 3,600 internet users in eight countries about the problem of movie piracy. It complained that almost a quarter of them (24%) had downloaded a movie, and 17% were likely to download movies in the future. If it follows the trail blazed by the Recording Industry Association of America (RIAA), the MPAA could soon end up taking file sharers to court.

The personal computer is, of course, a wonderful copying machine, and it doesn't just allow people to copy their own photos and texts. There is lots of software that enables users to duplicate or rip their CDs and DVDs, and while they can do this for legitimate reasons, they can also share these files with friends, or put them online. Indeed, it's hard to believe that PCs would be as popular as they are if they did not allow this kind of thing.

Perhaps the computer industry has people who believe that consumers will buy PCs to copy music, movies and anything else they fancy, but will magically draw the line at copying software. But it sounds unlikely to me.

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