Kinda. It's confusing. Windows RT is supposedly "Windows 8 on ARM", a restricted version of Windows 8 where Win32 is not available to non-in-house developers (applications must be developed using WinRT a replacement API not to be confused with Windows RT as WinRT is also available to Windows 8 and Windows Phone 8); all applications must be distributed via the Windows Store; the fate of the Windows 8 desktop is unclear (though it won't be very useful if there); a bunch of software or capabilities are unavailable in RT (Windows Media Player, Media Center, Remote Desktop, Homegroup, ...).
The simplest way to think about it is probably to think that WindowsRT is to Windows 8 as iOS 9 (iPad) should be to OSX 11 should the current trends of the latter pair keep going
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Kinda. It's confusing. Windows RT is supposedly "Windows 8 on ARM", a restricted version of Windows 8 where Win32 is not available to non-in-house developers (applications must be developed using WinRT a replacement API not to be confused with Windows RT as WinRT is also available to Windows 8 and Windows Phone 8); all applications must be distributed via the Windows Store; the fate of the Windows 8 desktop is unclear (though it won't be very useful if there); a bunch of software or capabilities are unavailable in RT (Windows Media Player, Media Center, Remote Desktop, Homegroup, ...).
The simplest way to think about it is probably to think that WindowsRT is to Windows 8 as iOS 9 (iPad) should be to OSX 11 should the current trends of the latter pair keep going
See http://www.theverge.com/2012/10/17/3514556/windows-8-vs-wind... for more info (and a hint as to how confusing it is)