Web-based programs like Google's Gmail will force people to buy into locked, proprietary systems that will cost more and more over time, according to the free software campaigner

The concept of using web-based programs like Google's Gmail is "worse than stupidity", according to a leading advocate of free software.

Cloud computing – where IT power is delivered over the internet as you need it, rather than drawn from a desktop computer – has gained currency in recent years. Large internet and technology companies including Google, Microsoft and Amazon are pushing forward their plans to deliver information and software over the net.

But Richard Stallman, founder of the Free Software Foundation and creator of the computer operating system GNU, said that cloud computing was simply a trap aimed at forcing more people to buy into locked, proprietary systems that would cost them more and more over time.

"It's stupidity. It's worse than stupidity: it's a marketing hype campaign," he told The Guardian.

"Somebody is saying this is inevitable – and whenever you hear somebody saying that, it's very likely to be a set of businesses campaigning to make it true."

The 55-year-old New Yorker said that computer users should be keen to keep their information in their own hands, rather than hand it over to a third party.

His comments echo those made last week by Larry Ellison, the founder of Oracle, who criticised the rash of cloud computing announcements as "fashion-driven" and "complete gibberish".

"The interesting thing about cloud computing is that we've redefined cloud computing to include everything that we already do," he said. "The computer industry is the only industry that is more fashion-driven than women's fashion. Maybe I'm an idiot, but I have no idea what anyone is talking about. What is it? It's complete gibberish. It's insane. When is this idiocy going to stop?"

The growing number of people storing information on internet-accessible servers rather than on their own machines, has become a core part of the rise of Web 2.0 applications. Millions of people now upload personal data such as emails, photographs and, increasingly, their work, to sites owned by companies such as Google.

Computer manufacturer Dell recently even tried to trademark the term "cloud computing", although its application was refused.

But there has been growing concern that mainstream adoption of cloud computing could present a mixture of privacy and ownership issues, with users potentially being locked out of their own files.

Stallman, who is a staunch privacy advocate, advised users to stay local and stick with their own computers.

"One reason you should not use web applications to do your computing is that you lose control," he said. "It's just as bad as using a proprietary program. Do your own computing on your own computer with your copy of a freedom-respecting program. If you use a proprietary program or somebody else's web server, you're defenceless. You're putty in the hands of whoever developed that software."