Google co-founder Sergey Brin said Windows and other traditional PC operating systems are "torturing users" at Google's Chrome OS launch event Wednesday, where the company claimed 75 percent of business users can be converted from Windows to Chrome OS right away.

Google is partnering with Samsung and Acer to ship laptops based on Google's browser-turned-operating-system on 15 June, it was announced at the Google I/O conference. In a briefing with reporters afterward, Brin was asked how many Google employees still use Windows. As a rough guess, he said it's about 20 percent. The rest must use Macs or Linux. But by next year, Brin hopes the vast majority of Googlers will be doing their work on Chrome OS.

"I don't think there is anything inherently wrong with Windows," Brin said. "Windows 7 has some great security features."

But Chrome OS, by putting most of a user's applications and data on the web with some offline capabilities, presents a "stateless" model that Brin believes will eliminate complexity for users and IT departments by un-tethering people from machines that are difficult to set up and manage.

"With Microsoft, and other operating system vendors, I think the complexity of managing your computer is really torturing users," Brin said. "It's torturing everyone in this room. It's a flawed model fundamentally. Chromebooks are a new model that doesn't put the burden of managing the computer on yourself."

Google executives said they surveyed 400 companies and found that with a combination of web applications, offline access to Google Docs and other services, and applications delivered through virtualisation software, businesses could move 75 per cent of their users onto Chrome OS devices.

Microsoft (and even Apple) could probably come up with a survey showing exactly the opposite. But Google does have an interesting plan to market Chrome OS devices, including partnerships with VMware and Citrix to deliver remote access to enterprise applications.

Chrome OS is basically nothing more than the Chrome browser on top of a stripped-down version of Linux, with no need to install antivirus software because of Chrome's sandboxing security, and cloud-based backups to restore data on the off chance you get a virus. All user data is encrypted by default.

While the devices are primarily designed to surf the web, the laptops will have a file system and some offline access to key productivity applications.

Devices from Samsung and Acer will be sold at Best Buy and for between $350 (£215) and $500, but businesses can get the devices in a package for $28 per user per month, which includes support and hardware replacements. A similar deal for $20 per user per month is available to schools.

Samsung will offer a $429 version with a 12.1-inch screen and Wi-Fi, and Verizon will ship a 3G version for $499. An Acer device with an 11.6-inch screen will start at $349.

Google made quick mention of a partnership with VMware and Citrix to deliver browser-based access to business applications, but said no more details would be revealed until later in the day during a panel discussion on enterprise computing. How the integration with VMware and Citrix will work, and what it will cost, are questions we'll be looking to get answered.

Thousands of users have tested Chrome OS laptops in a beta period, although more than a million applied for the free trial notebooks. Google characterised the reaction as overwhelmingly positive but acknowledged that users felt the computers should be faster, afford better access to USB devices and provide offline access to email, calendar and Google Docs.

With the 15 June launch, Google will meet all of those concerns by upgrading to Intel dual-core processors, providing the offline access to Docs, Gmail and Calendar, integrating with USB devices and SD cards, and providing a file system to view movies, pictures, documents and other files. A built-in media player will play movies and music.

Google will also provide desktop versions in a small box that connects to a monitor, keyboard and mouse, but no availability date was given.

Users will be encouraged to back up data and settings to cloud-based services - whether they be Google services or those from the likes of - to ensure that applications and data are available from any device and allow users to upgrade computers without a cumbersome installation process.

"We really want to make it possible for users to store their important data in the cloud and access it anytime, anywhere," said Sundar Pichai, vice-president of Chrome at Google.

The success of online services shows that many users do trust their data to the cloud. Whether enough will do so to replace 75 percent of Windows computers is a point that will probably be debated for quite some time.

But there are clear benefits. Google says the computers start up in seconds, resume from sleep mode almost instantly and have battery life of either 6.5 hours or eight hours. On a first use, it only takes a few minutes to set the computer up.

"Each time you open the lid, before you can move your fingers and touch the keyboard, you're connected to the web," Pichai said.

Google's Chrome OS announcements came on the second day of its annual developer conference. The first day focused on Android, Google's OS for phones and tablets. Some have doubted the viability of Chrome OS given the giant market presence of Android. Whether Google can build two successful operating systems is something we are about to find out.