Windows 7 launch countdown begins

If you're eager to get hold of a copy of Microsoft's latest operating system, Windows 7, you only have a few more hours to wait.

The operating system officially goes on sale at midnight on Wednesday with some stores such as PC World on London's Tottenham Court Road planning to open their doors to customers in the wee hours of Thursday morning.

The successor to the much-derided Windows Vista, Windows 7 comes in six flavours, among them Home Premium, Professional and Ultimate. Other editions are aimed at the developing world and enterprise customers.

Windows - a timeline

Home Premium officially costs £79.99 but can be bought on the Amazon website for £64.68. Professional costs £148 on the same site, and Ultimate is £159.98.

Some customers have already got their hands on Windows 7 as several vendors sent out pre-ordered copies early to get around the postal strike planned for this week.

Windows 7 - the waiting is (nearly) over

Though Windows 7 bears a passing resemblance to Windows Vista, Microsoft has deliberately stripped its new operating system down so even PCs with a low specification should be able to run it.

There are few major design innovations in Windows 7, though the process of setting up home networks has been simplified, and a 'snap-to' feature that enables you to put two open windows side-by-side quickly has been introduced.

The new OS also supports multi-touch technology, so expect to see a glut of touchscreen PCs hitting the market before Christmas.

How much do you know about Microsoft's OS? Take our History of Windows quiz