Google has long worked on expanding its reach beyond mere Internet search. And as many had suspected, it confirmed late Tuesday night that it plans to develop a lightweight operating system based on Linux and Web standards for personal computers.

Why? Well, Google's standard response to any question about why it's working on something other than search is to declare that any product that helps people get on the Web, and enjoy their experience on the Web, benefits Google's advertising customers in that more Web users equals more Google searches.

Yet, Chrome OS represents something more. There's a competitive impact that can't be ignored, no matter how often Google insists that it's in this world to do good rather than inflict pain on other corporations.

Few details were available Wednesday concerning one of the most important and ambitious projects Google has ever undertaken. Sources familiar with the Chrome OS project say Google engineers have only been working on the project in earnest since the beginning of the year, so there's likely a lot that still needs to be ironed out.

Chrome OS is the byproduct of Google thinking it can do better than Windows, Mac OS X, the various flavors of Linux, and even its own Android operating system. It's long been obvious that the world has changed from a personal computing model built for individuals working offline or businesspeople sharing files across a workplace to one where the consumer/business lines have blurred and people are expected to be online anywhere and everywhere.

Accompanying that shift has been the decreasing importance of processing power and operating system complexity. For years, the dirty secret of the computer industry has been that most people don't use nearly the amount of headroom provided to them by modern microprocessors and operating systems.

After all, if you're searching the Web, sending e-mail, typing up documents, touching up photos, and updating your Facebook status--hardly an uncommon usage model--you're more concerned with speed and battery life than raw power. Those still playing Doom or editing video will always need something more robust, but most people do spend an awful lot of time in the browser and have embraced smartphones and Netbooks as a way of staying online on the go.

Google's general idea seems to be twofold. First, it wants to make it easier for regular people to use a computer by making an operating system that is fast, secure, and lightweight enough to run on portable devices.

Sources familiar with Google's plans for the Chrome OS said that the company is working on a new method of "windowing," or switching between multiple applications. Google also believes that the whole idea of storing your files and applications in folders is an archaic way of organizing your data, and plans to unveil a new user interface that handles things a little differently.

Secondly, Google believes that through the use of Web standards like HTML 5--promoted heavily during its recent Google I/O conference as the development platform of the future--software development on a browser-based OS will be easily understood by developers reared in the Web 2.0 era.

Google brings much more to bear than Palm, however. It has an entire suite of Web applications and services that already form much of what you want a computer to do: send e-mail, compose documents, edit photos, and, of course, browse the Web.

But why does Google think it needs two operating systems to address this evolving usage model? Much of the language used to introduce Chrome OS could have been pulled from a blog post two years ago introducing Android, Google's lightweight Linux-based open-source smartphone operating system.

Just a few months ago Google's Andy Rubin declared Android to be "a revolution" that would help Google conquer the write-once, run-anywhere goal that has eluded the non-Microsoft software community for so many years. And Google executives have endorsed the concept of other companies building things other than phones based on Android.

However, Android appears to now occupy a different role in Google's thinking. According to Tuesday night's blog post, "Android was designed from the beginning to work across a variety of devices from phones to set-top boxes to netbooks. Google Chrome OS 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."

As noted, there are an awful lot of details that still need to surface before we can glean Google's true intent with Chrome OS, not to mention the potential impact. Google said it plans to release the code for Chrome OS later this year, with the expectation that devices based on the OS could arrive in the second half of 2010.

But one thing is for sure: Google's ambitions are boundless. The company is proposing to do nothing less than rewrite the rules that govern personal computing.