Google revealed more details of its forthcoming operating system, Chrome OS, and launched a pilot program for advance users in a press conference in San Francisco yesterday.

The company announced that devices carrying the operating system will be on sale in the US from “mid-2011”. It revealed that PC vendors Acer and Samsung and chipmaker Intel will provide the hardware, although other partners will follow.

Although Chrome OS is designed specifically for consuming applications and information from the Internet – “nothing but the web” is the system’s tagline – users are able to work offline.

The company revealed that the OS is designed for devices with full keyboards, not tablets. Google is testing the operating system using a purpose-built laptop, codenamed Cr-48.

Some of these devices are available for testing under pilot program. This is program open to individuals but some businesses, including American Airlines, are testing the product too, Google revealed.

Speaking at the conference, Google and former Sun Microsystems CEO Eric Schmidt explained the operating system in the context of the move towards the “network computer”, a concept that Sun (and Oracle) used to champion in the 1990s.

He said while it was an untenable proposition back then, technological advancements hadve network-based user device possible today. “The disks are that much faster, the networks are more reliable,” Schmidt explained, as reported by gadget website engadget.