MOUNTAIN VIEW, Calif. — Google and Microsoft have long competed for talent and the attention of Wall Street, but the two have never taken each other head on. Google's main business is search. Microsoft's is Windows and Office software.

This year, Google signaled it is ready to take Microsoft on on its home turf with an operating system called Chrome OS. Microsoft is like Starbucks when McDonald's started selling espresso.

Built for netbooks, Chrome OS is a free operating system designed to take users to a Web browser. It promises to turn a computer into a Web-only machine, much like a television that shows only video.

"We're dealing with legacy systems when all people need is the Web," said Caesar Sengupta, product manager director for Chrome OS at Google.

So Google is betting Chrome OS will ride the explosion in cloud computing — where software will be stored on the Internet instead of on a computer.

While observers see Web-based cloud computing as the way of the future, however, some question whether Chrome OS has come too soon.

"I do think it's the future. I just don't think it's the near-term future," said analyst Rob Enderle of The Enderle Group, a consultancy in San Jose, Calif.

Microsoft declined to talk about Chrome OS in interviews. The company put out a statement reiterating how Windows 7 sells twice as many copies as other operating systems.

"From what was shared (about Chrome OS), it appears to be in the early stages of development.

From our perspective, however, our customers are already voicing their approval of the way Windows 7 just works — across the Web and on the desktop, and on all sizes and types of PCs," the statement said.

No computer-makers have announced plans to sell computers with Chrome OS yet, but Google is planning on netbooks with Chrome OS to start selling in the fourth quarter of 2010. It recently demonstrated how the software works and began sharing the code with the open-source development community last month.

Chrome OS began as just Chrome, a Web browser from Google.

"The Web was evolving, Web apps were evolving, but not a whole lot of stuff was happening on the browser," Sengupta said. "That's why we did Chrome."

At its most basic, a computer-operating system powers a computer, connects it to a network and provides the software to connect the computer to monitors, keyboards, printers and other devices.

Windows also manages software stored on the computer, such as Office, the Web browser, an instant messenger, iTunes and Photoshop. The success of Windows, and growth of Microsoft, was driven, in part, by the number of applications available for Windows, and not available for its competitors.

Chrome is built to store nothing on a computer, nary a photo, a Word document or song. The engineers are still working on how to connect it to a printer.

The one thing Chrome does is take the users directly to a Chrome Web browser screen and it does it fast. In early demonstrations on prototype netbooks, Sengupta said it took seven seconds to boot — the time required to get from pushing the power button to opening a browser screen.

"We want to get to a point where when you open a computer, it's on," he said.

Sengupta acknowledges the shortcoming of the Web is that it does not work offline, and that it is difficult to play high-quality PC games. It won't run iTunes, but it will have streaming music such as Pandora.

Sengupta says users can depend on Web apps instead of applications stored on a computer — go to Google Docs, for instance, instead of Microsoft Word. He says they have 100 million Web apps to choose from. (Those apps also generally work on Windows-run computers.)

The other way Chrome OS differentiates itself is on price. It's free to users and to netbook-makers who want to install it on computers. Several computer manufacturers declined to comment on whether they would sell netbooks with Chrome OS.

Even though Chrome OS is free, Google expects it to generate revenue anyway — by increasing the market for search advertising. A faster way to connect to the Internet, Sengupta said, would encourage people to use the Web more and consume more ads.

"What's good for the Web is good for Google," Sengupta said. "I live in Sunnyvale (Calif.). There are three routes I can take. But I have to boot up the computer. If we make it easier to get to the Web, you will use it a lot more."

It's ironic Google has now built an operating system that only browses the Web, when Microsoft has spent more than a decade battling antitrust concerns in the U.S. and Europe because it bundled its Internet Explorer browser with Windows.

Microsoft last week agreed to a settlement in Europe to give users easier access to competitors' browsers on Windows.

Analyst Enderle predicts the optimal infrastructure needed for Chrome OS — a high bandwidth wireless network and robust cloud-based applications — will not be in place until after 2015.

"This is a product that will best exist in a world that doesn't exist yet," he said.

Until then, a Chrome OS user would have to give up the ability to use a computer offline, such as on the airplane.

It would also be difficult to differentiate a Chrome OS netbook from a Windows netbook on price, considering wireless carriers have been offering netbook for as little as $50 this holiday, he said.

"Chrome OS' problem is, well, jeez, with a netbook today you can kind of have your cake and eat it, too," Enderle said. "You can do all the online stuff that Chrome OS promises, then you can do all the offline stuff that you're going to do for the next five to 10 years."

Via McClatchy-Tribune News Service.