So, Microsoft’s new operating system, Windows Vista, has arrived. But what does that mean for ordinary computer users like you and me?

There’s a lot more to it than just some swish new special effects, which look nice but don’t really add much. The important changes to Windows have happened under the bonnet, in the depths of the computer code that you never see.

Microsoft claims Vista is much more stable and dependable than XP. Every user of the computer is awarded certain "privileges", an old concept in computer terms but one that will be new to most Windows users.

This means that you can only do certain things in Windows, before the computer will ask you for a password to ensure that you know what you’re doing, and are who you say you are.

The added advantage of the privilege system is that parents can set up new accounts for their children, and can administer which privileges the younger ones have access to.

Those who can be trusted may be granted full access to everything. Untrustworthy kids can be restricted to certain programs, no chat, and limited web access.

Those in the dog house can be (temporarily, if need be) banned from the web and email altogether.

The system itself should be more reliable, thanks to the new way Windows is put together.

Programs now run in their own self-contained chunk of computing, which means (in theory) that if and when they crash, they won’t force the entire computer to crash as well.

Unresponsive programs should now be easy to exit or restart, without needing to reboot the computer.

One of the smartest new ideas is instant memory expansion. You’ve probably encountered USB memory sticks, the modern equivalent of floppy disks.

Usually they’re several hundred megabytes big, or even several gigabytes. You can store plenty of information on them, and they are fast, cheap and convenient.

Now you can use them for something else in Windows Vista.

Grab a spare memory stick, plug it into your computer, and zap! Suddenly your computer has more memory at its disposal, which it can use to run programs more efficiently, or just run more programs at the same time.

This is seriously impressive technology and makes the previously dull memory stick a much more interesting piece of kit.

Along similar lines are the designs of some of the brand-new laptops expected to arrive in the shops soon. These have been built from scratch to support Vista, and they include a number of innovative new ideas.

Windows SideShow is one such idea. It means your laptop can have a second little screen built into the lid, on which you’ll be able to perform basic tasks without having to actually open the computer and switch it on. Of course, using this screen and the associated components will draw battery power, but even so it could be a time-saver for regular travellers.

On top of all this is the new Aero interface, only supported by the most recent computers with powerful graphics cards. It sports translucent windows, swish animation effects, and a smarter-looking task bar at the bottom of the screen.