From early in their company's history, Google's founders, Larry Page and Sergey Brin, wanted to develop a computer operating system and browser.

They believed it would help make personal computing less expensive, because Google would give away the software free of charge. They wanted to shrug off 20 years of accumulated software history (what the information technology industry calls the "legacy") by building an OS and browser from scratch. Finally, they hoped the combined technology would be an alternative to Microsoft Windows and Internet Explorer, providing a new platform for developers to write Web applications and unleashing the creativity of programmers for the benefit of the masses.

But despite the sublimity of their aspirations, Eric Schmidt, Google's chief executive, said no for six years. Google's main source of revenue, which reached $5.5 billion in its most recent quarter, is advertising. How would the project they envisioned support the company's advertising business? The question wasn't whether Google could afford it. The company is wonderfully profitable and is on track to net more than $5 billion in its current fiscal year. But Schmidt, a 20-year veteran of the IT industry, wasn't keen on shouldering the considerable costs of creating and maintaining an OS and browser for no obvious return.