(Mashable) -- Microsoft is set to unveil the next generation of Windows today. The new operating system, currently known as Windows 8, is the tech giant's attempt to regain ground that it has lost to Apple, which surpassed Microsoft last year as the world's most valuable company. It isn't the MacBook or Mac OS X Lion that has Microsoft executives worried, though. It's the sheer dominance of the iPad. The iPad hasn't skipped a beat since its debut last year. Thanks to Apple's ingenuity, a shockingly low starting price and a strong marketing campaign, the device has sold more than 25 million units in less than a year and a half. More importantly, it has defined a whole new category of consumer devices. And it dominates that category with an iron fist.
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Apple iPad has sold more than 25 million units in less than a year and a half
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Nothing has emerged as the alternative to the iPad -- a problem and opportunity for Microsoft
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Windows 8 will be unveiled at the Microsoft Build conference Tuesday
@placeholder competitors have come and gone, but none have been able to make a dent in the iPad's rapid growth.