The new tablet line, named Surface, includes a consumer device aimed directly at the Apple iPad, and another, larger machine designed to run the full suite of Windows software. Both include a keyboard that doubles as a cover for the device, and both will be powered by the new Windows 8 operating system.
The move breaks with Microsoft's operating model of the past 37 years, which has relied on computer manufacturers to make and market machines running Windows. It could throw the world's largest software company into direct competition with its closest hardware partners such as Samsung Electronics and Hewlett-Packard.
However, the success of Apple in recent years has underscored the benefits of an integrated approach to hardware and software, and Microsoft CEO Steve Ballmer said on Monday that the company "didn't want to leave anything uncovered" as it rolled out Windows 8.
The new software is the biggest overhaul of Windows in years, and features a new interface, dubbed "Metro", and many touch-friendly features. It is scheduled to be available for the Christmas shopping season.
A lighter, thinner version of the Surface tablet, based on chips designed by ARM Holdings, will be the first to market at the same time as the general release of Windows 8, and will feature Microsoft's popular Office suite of applications.
It is comparable to Apple's new iPad, heavier but slightly thinner. It has a 10.6 inch screen and comes in 32GB and 64GB memory sizes.
A second tablet, running on traditional Intel Corp <INTC.O> chips, will be heavier and thicker but come in 64GB and 128GB models. That will be available about three months after the ARM version, Microsoft said.
The company gave no details on pricing, except that they would be competitive with comparable ARM tablets and Intel-powered Ultrabooks.
Microsoft shares rose slightly in after-hours trading. They closed down 0.6 percent at $29.84 in the regular Nasdaq session.
Sales of tablets are expected to triple in the next two years, topping 180 million a year in 2013, easily outpacing growth in traditional PCs. Apple has sold 67 million iPads in two years since launch.
copyright @ Thomson-Reuters 2012