The founder of the Free Software Foundation has criticised Google's Chrome OS, claiming it will force PC users to put their data at risk by storing it in the cloud rather than on a machine.

Richard Stallman, who also created the operating system GNU, told The Guardian the OS will "push people into careless computing" as by storing data in the cloud, PC users will lose the legal right to their data and the ability to control it.

"In the US, you even lose legal rights if you store your data in a company's machines instead of your own," he said.

"The police need to present you with a search warrant to get your data from you; but if they are stored in a company's server, the police can get it without showing you anything. They may not even have to give the company a search warrant."

Stallman said he expected many people "will continue moving towards careless computing, because there's a sucker born every minute.

"However, as long as enough of us continue keeping our data under our own control, we can still do so. And we had better do so, or the option may disappear."

Stallman claimed that, in essence, Google's OS is "the GNU/Linux operating system. However, it is delivered without the usual applications, and rigged up to impede and discourage installing applications."

Google officially unveiled the OS last week, some two years after it was first mooted. The system, which is currently being trialled by firms and a handful of consumers, stores as little data as possible on the machine itself, and instead, relies of a web connection to store data online in Google's servers.

Google has yet to reveal if or when it plans to produce its own laptops running the operating system. However machines from Acer and Samsung that feature the OS are expected to be made available in mid-2011.

See also: Opinion: can Google Chrome OS save the netbook?