Windows Vista has launched, five and a half years after its predecessor, Windows XP. Four versions are available to consumers as full versions and upgrade packs; Home Basic, Home Premium, Business and Ultimate.

Microsoft isn't quite trying to ape the huge launch of Windows 95, complete with the Rolling Stones and 'Start me up' ad campaign. But the hype is definitely there. The company's slogan for the new operating system is 'The wow starts now' - Microsoft hopes Vista will impress prospective purchasers with its appearance.

Bill Gates will be speaking at the first Vista launch event - in New York's Time Square. You can see it live or delayed here (from 21.45 GMT). We'll be reporting live from the UK events. PC World's Tottenham Court Road store is opening at 6am, while Bill Gates will be clocking up the air miles - he's addressing the press at The British Library at 9.30am.

Other hardware and software vendors are also gearing up for the release. We reported on Saturday how you can now buy systems configured with Vista. ATI has also released Catalyst 7.1 , its driver release for Vista, with Nvidia expected to follow suit with updated drivers for its top-of-the-range DirectX 10-compatible cards.

What you'll need

Microsoft recommends a minimum specification of 512MB of memory and an 800MHz processor to run Windows Vista. However, we'd suggest you should have at least 1GB of memory to run the new system even though we've had it running on less. You'll also need a decent graphics card if you want to run the new Windows Aero-stylised interface.

The full requirements are outlined at the Windows Vista website. There, you'll also find the Windows Vista Upgrade Advisor , a downloadable app which will tell you if your PC is powerful enough to run Vista. Newer PCs have already been marked with Vista Capable and Vista Premium Ready stickers to designate they can run different versions of the operating system.

The Windows Vista website has changed to be the Microsoft Windows homepage as the software begins its lifespan. Our brand new sister title, Windows Vista: The Official Magazine , is also beginning its life and will be on sale from Wednesday.