It is called Windows 8, but it might be simpler to think of it as Windows 7+1. Underneath everything you will see at first is the same Windows that anyone who has been using Windows 7 since October 2009 is used to seeing.
But it is that +1 you will see first – and this is where, for many people, the surprise may start. Microsoft has completely rethought the initial experience – the process by which we start interacting with a computer when its screen comes on – and replaced the "desktop" with large tiles that you swipe with a finger or mouse from side to side. Modern UI, as it is called, involves big tiles without the fussy "close" or "minimise" or "maximise" buttons.
I have been using the final version of Windows 8 for several months on a Samsung tablet. After a while, the new version feels relaxing – natural, even.
The start screen, as Microsoft calls it, consists only of those big tiles and completely replaces the desktop you first see on Windows. But that old Windows desktop is still there – it is just hidden one layer down – and if you want to jump down into it, there is a perfectly good fireman's pole, a tile called Desktop. Click or touch that and you are in Windows 7.
The start screen houses whatever you want it to on those tiles, which can be live, and so the weather tile shows the forecast, the mail tile shows the mounting unread toll, your calendar tells of the next meeting. It is a helpful, innovative experience. You can "pin" Windows apps to the start screen and you can also download free or paid apps from the built-in Windows Store.
Using Modern UI apps does take some getting used to. It is a mini-malist experience that does away with the clunky windows and scroll bars of the old Windows. The screen is filled with whatever you are doing, whether it is Internet Explorer, the "social" app (which ties together your social networks in one place) or the mail app.
The control buttons are hidden and the navigation to get you around the rest of the system – back to the start screen – is squirrelled away on the right-hand side of the screen.
But it is at this point that the +1 nature of this all gets slightly uncomfortable. If, for example, you want to change the date on your computer, you cannot do it in the big Modern UI tiles. You will have to take the fireman's pole down to Windows 7. And there it is all suddenly the same again. It is like Bobby stepping out of the shower in Dallas. All those close, minimise and maximise buttons, title bars on windows, resizing – all that stuff you have been doing since Windows 3.1.
You will find that Windows 8 runs quicker, more securely and much more like the operating systems we are used to on tablets and smartphones, which are themselves becoming the principal way people do computing. So, for Microsoft, Windows 8 is a huge leap forward, but it is doing it while holding all the baggage of the old Windows.
Expect some cries of pain as people adjust. But, viewed more broadly, it could not do anything else: the desktop paradigm is getting tired and the tiles approach is fresh and quickly becomes intuitive. That Windows 8 will be a huge hit in terms of sales is a given. What will be fascinating to watch is how it is received. – © Guardian News & Media 2012