With such a radical departure from the Windows format we've all used for the last 17-odd years since Windows 95 was launched, we thought it was time to take stock and see how Windows 8, reviewed, compares with Apple's Macintosh operating system - OS X Mountain Lion, also reviewed - and find out whether it's time to switch. See also: Windows 8 Advisor

In releasing Windows 8, Microsoft has taken a huge step towards a unified operating system experience across PCs, laptops, tablets, and smartphones. Where once small icons and start menus populated the Windows desktop, the simplified Modern user interface, replete with live tiles and controlled with touch gestures, is proving an unfamiliar and often confusing new landscape.

Improvements behind the scenes are noticeable, but redesigning the way that users interact with their machines was always going to be a difficult proposition. Don't forget, though, that the traditional desktop remains, albeit without a start menu.

Response to Windows 8 has been mixed. Microsoft claims to have sold sixty million copies which, if true, is a healthy figure. However, there has also been a lot of negative press about the frustrating learning curve that Windows 8's new interface requires and other reports of customers (particularly businesses) exercising their downgrade rights and switching to Windows 7 when buying new PCs. See also: How to uninstall Windows 8

One of the problems Windows 8 has faced is being a touch-based OS often running on machines with only a keyboard and mouse for input. It's certainly possible to use the Modern UI with a keyboard and mouse, but it can take more clicks to accomplish a task in Windows 8 than in previous versions.

We’re now seeing PCs manufactured specifically with the Modern UI in mind, featuring touch-screens, gesture-supporting touchpads, and even some unusual designs that enable laptops to transform into tablets. Finally, it's possible to experience Windows 8 as Microsoft intended.

Since it isn't possible to run older applications in the Modern UI, Microsoft has had no choice but to retain the traditional desktop environment, making Windows 8 an operating system of two halves. In this feature we're going to compare both sides of Windows 8 against Mountain Lion.

In order to make this more manageable, we're comparing the two operating systems as they arrive out of the box, with no third-party browsers, email clients, photo managers, or anything else installed. To evaluate Windows 8, we used a Lenovo IdeaPad Yoga 13 - a 13in ultraportable laptop whose screen folds back 360 degrees so it can also be used as a tablet - and for OS X, we sourced a 13in Macbook Air.

We'll look at every facet from the obvious interface design to the bundled apps, security, file sharing and more.

Windows 8 has been out in the wild for five months now, had its preliminary patches applied, and seen the introductory £15 upgrade offer consigned to history. Now things get serious: so it’s Microsoft vs Apple, Windows 8 vs OS X Mountain Lion. Read on to find out how two different design concepts stand up to the mundane reality of everyday computing.

Next page: Window 8 vs Mac OS X - Interface Design

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