Microsoft unveiled a tablet called Surface on Monday, in a move to rival Apple's massively successful iPad. The world's largest software maker is on track to launch its touch-friendly Windows 8 operating system this autumn and wants to make a big impact with its own device to kickstart demand.

The tablet will come in two versions, one running on traditional Intel Corp chips, and another using ARM Holdings. Both will have a fold-out cover that becomes a keyboard. A prototype was demonstrated by Microsoft Chief Executive Steve Ballmer at an event in Los Angeles. The tablets will be available when Windows 8 ships later this year, according to a Microsoft statement.

No details on pricing were mentioned, except that it would be "comparable" with current ARM tablets and Intel-powered Ultrabooks.