It doesn't feel like it, but Windows 7 is coming up to its third birthday. However, there'll be no party as Windows 8 is due to be launched later this year, and will be pre-installed on just about every new PC and laptop.

Windows 8 is a crucial operating system for Microsoft as, unlike 7, Vista and even XP before that, this latest OS isn't a mere evolution of the last version. No, Windows 8 is as different from Windows 7 as Windows 95 was from Windows 3.1 before it.

In this age of touchscreens and gestures, the keyboard and mouse almost seem antiquated and clunky, and Windows 7 looks and works pretty much exactly the same as Windows 95 did almost 17 years ago.

17 years is a very long time in computing terms, so you could argue that Windows 8 is long overdue. However, as you'll see, there's an equal number of arguments that a touchscreen interface makes no sense on a laptop, and possibly a desktop PC too.

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One OS to conquer them all

With Windows 8, Microsoft's aim is to have one operating system that runs on all your devices, be that a smartphone, tablet, laptop or PC. Regardless of screen size or how you interact with the device, Windows 8 will scale perfectly. That's the theory, but is it madness… or genius?

We've tried the new 'Metro' interface on a range of computers, including touchscreen all-in-one PCs, laptops and tablets, and were surprised at just how well the interface copes with a huge range of screen sizes from 10in right up to 27in. Although there's no Windows 8 for smartphones yet, Windows Phone 7 already has the Metro UI (user interface), so we already know that it works well. Xbox 360 owners will also be familiar with the tiled Metro UI, as it was rolled out as an update in late 2011.

There's no real integration with Windows Phone 7 so you still have to install Zune to sync your handset. This is likely to change (and Zune is likely to disappear) when the next version of Windows Phone is released. This could be in summer 2012, or it could coincide with the release of Windows 8 itself, which is purported to be in October. We'd be surprised if it isn't called Windows Phone 8; Microsoft's codename for the update is Apollo.

Windows 8 on 10in tablet

Resistance to change

Most computer users resent even tiny changes to interfaces, struggling to cope with programs and settings being renamed or moved. Facebook is a classic example, as it is constantly updating and refining its website. With each change comes a barrage of protest, and the change from the classic Windows desktop to Metro will no doubt lead to people returning their new purchase to the shop where they bought it.

Trouble is, without change there is no progress. As long as you're willing to at least try the new interface - we'll show you the ropes to make things easier - you'll quickly feel at home and will appreciate many of Windows 8's new features.

Even if your computer doesn't have a touchscreen, Windows 8 can be controlled with a mouse, so don't let that put you off giving it a try.

The cloud

One of Windows 8's main themes is integration with online services. As well as the all-new Store where you can download Metro-style apps, you can also connect apps to your existing online accounts. For example the Mail app can pull in email from Gmail, and the Photos app can display images from Facebook. All your settings and personalisation are stored in the cloud as well, so you can log onto another Windows 8 computer using your Microsoft account and everything will look and work just like your computer does.

NEXT PAGE: The Metro UI explained

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