Instead of backing up your files to a disk connected to the computer, online backup software such as Webroot Secure Backup copies the files to a computer on the internet.

These servers are themselves duplicated, so that if the worst does happen to your computer, your files and documents can be easily restored.

Of course, the disadvantage is speed. While backing up to a local disk is quick, doing the same over the internet is much slower simply because it takes time to move the data from one place to another. It took 10 minutes to copy our 25MB of test files, compared with a couple of seconds to copy the same to a USB memory key.

It uses a step-by-step process to do the backup – once you've logged in (you need to set up an account when you download the software) it offers the choice of backing up locally or online, or restoring from a local or online backup. The user can choose between a menu of preset files to copy (such as pictures or internet favourites) or choose specific files or folders.

When restoring, the program displays a calendar on which backup dates are circled, and clicking one shows the backups made on that day, from which specific files or folders, or entire disks, can be chosen to be brought back.

As you might expect from the name, everything is done securely. The data is scrambled before it leaves the computer and again at the remote end. Users can even request a secure password (although this can't be recovered by Webroot so if you lose it you're stuck).

It costs £15 per year for 2GB of files, but most people will want more than that – 10GB costs £25 and 50GB £50. That's slightly more than rival software Carbonite, but Webroot Secure Backup's ease of use just about has the edge here.

One qualm is that you need to be logged in, with an active internet connection, even to make a local backup to USB key or hard disk, which could be a pain for notebook users. Still, this is a good choice of backup software.