SAN JOSE, Calif. - Google has announced that it is developing a personal computer operating system that will be an extension of its Chrome browser, optimized for Web users and targeted at the rapidly growing netbook market.

Sundar Pichai, Google vice president of product management, and engineering director Linus Upson said in a post on Google's blog that "speed, simplicity and security" are key to the new Google Chrome OS. The code will be open-sourced later this year and the first netbooks running the new system will be available in the second half of 2010, the pair wrote.

Google's move takes on Microsoft and its dominant Windows operating system at a time when the Mountain View-based company is struggling to gain a foothold in the lucrative office applications market dominated by Microsoft's Office suite.

Pichai and Upson said the Chrome operating system will be fast, taking little time to launch and put users on the Web in "a few seconds.

"The user interface is minimal to stay out of your way, and most of the user experience takes place on the Web," they wrote.

The pair noted that the operating system project is separate from the company's Android operating system aimed at smaller devices, from phones to netbooks. Chrome, they said, "is being created for people who spend most of their time on the web, and is being designed to power computers ranging from small netbooks to full-size desktop systems."

The Google Chrome OS announcement came on the same day Google dropped the "beta" label from applications like Gmail, Google Calendar, Google Docs and Google Talk as part of a strategy to expand sales to large companies and compete with Microsoft Office.

Like Windows, Office dominates its market with 70 percent market share based on the number of users compared to Google's 1 percent share.

The move to drop the 'beta' tag came after Google met resistance during a six-month push earlier this year to get corporate customers to sign up for the Google Applications Suite, the package of software that lets employees handle e-mail, word processing, calendaring and other typical office tasks with software that runs in a Web browser.

Nearly 2 million businesses use Google Apps, but most of them are smaller companies. In the blog post, Google noted "dozens" of big companies were customers.

(c) 2009, San Jose Mercury News (San Jose, Calif.).

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