Microsoft has revealed that there will be just three versions of Windows 8 when it is released and has finally explained just what's happening with Arm-based devices.

On its official blog the computing giant revealed that it wanted to make things simple for consumers and that is why there will be on three variations of the software.

Two of these variants will be for PCs sporting x86 processors – both 32 bit and 64 bit. These versions will simply be called Windows 8 and Windows 8 Pro.

When it comes to Arm-based devices, these machines won't be getting Windows 8 at all but something called Windows RT.

"Windows RT is the newest member of the Windows family – also known as Windows on ARM or WOA, as we've referred to it previously," explained Microsoft.

"This single edition will only be available pre-installed on PCs and tablets powered by ARM processors and will help enable new thin and lightweight form factors with impressive battery life."

It's worth noting that Windows RT won't be available in the shops. This is an OS that's going to get baked on to devices in the manufacturing stage, so will only come bundled with compatible hardware.

Slimmed down Microsoft

Microsoft continued: "Windows RT will include touch-optimised desktop versions of the new Microsoft Word, Excel, PowerPoint, and OneNote.

"For new apps, the focus for Windows RT is development on the new Windows runtime, or WinRT, which we unveiled in September and forms the foundation of a new generation of cloud-enabled, touch-enabled, web-connected apps of all kinds."

Speaking about Windows 8, Microsoft said: "Windows 8 has the flexibility you need – whether you're on an x86/64 or a WOA PC. You can use a touch screen or a keyboard and mouse – and switch anytime. It's beautiful, fast, and fluid design is perfect for a wide range of hardware."

So there you have it. Microsoft have gone for a very 'keep it simple, stupid' approach to its latest OS, presumably looking at the five versions of Windows 7 and deciding that streamlining was the way to go.