— Microsoft unveiled a radical redesign of its world-dominating Windows operating system Thursday, introducing a touch-enabled interface that attempts to bridge the gap between personal computers and fast-growing mobile devices powered by the company's fiercest competitors.
The debut of Windows 8 heralded the biggest change to the system since 1995, when the company first offered built-in Internet support. And with so much riding on it, the overhaul could be Microsoft's most important product since co-founder Bill Gates won the contract to build an operating system for IBM Corp.'s first personal computer in 1981.
To succeed, the new version will have to be innovative and elegant enough to attract consumers who've fallen in love with notebook computers, tablets and smartphones running software from Apple and Google.
"What you have seen and heard should leave no doubt that Windows 8 will shatter the perceptions about what a PC really is," Microsoft CEO Steve Ballmer crowed at a New York launching event.
The first PCs and other devices running Windows 8 were to go on sale Friday.
The software is designed for use on a variety of machines — desktop PCs, notebook computers and tablets, including Microsoft's new Surface tablet, the first computing device the company has manufactured after focusing almost exclusively on software for nearly 30 years.
The redesigned operating system represents an attempt to pull off a difficult balancing act as Microsoft maintains its highly profitable heritage in software while trying to get a foothold in the newer, more fertile field of mobile devices.
So far, the booming mobile device market has been defined and dominated by Apple's trend-setting iPhone and iPad, Google's pervasive Android software and Amazon's Kindle Fire tablets. Tablets have been undercutting the sales of desktop and laptop computers since Apple released its pioneering iPad in 2010.