We've been reviewing each new version of the CD/DVD Encyclopaedia Britannica for the last few years, and a thought occurs... Has so much really happened in the last year compared with the entire history of human existence? Is it really worth buying a new encyclopaedia every year just for some tweaks here and there and a year's worth of updates? Let's find out. (Three hours later...) Ah, yes, it seems that there's still mileage in knowledge. That's nice to know.

The interface of this latest version has been simplified, which is a good thing. You can now quickly scan through a list of every entry in the database or search for particular words - and the search is very quick. Cross-references are excellent, with, for example, an entry on alkaline-earth metals (bear with us) including links to a periodic table, descriptions of reactions, more general chemical and physical articles, biographies of chemists associated with the elements' isolation and so on. You get the same level of detail with many of the entries. We particularly liked the Internet section with its 'book of the year' features ('privacy concerns' was the topic for 2001, sensibly enough).

If you fancy a less structured route through this world of information, you can use the Knowledge Navigator to take you to a particular section ('The Mind and Emotions', 'Economics and Money', etc.) and just wander through, picking out topics of interest and scanning their contents before moving on. Alternatively, would-be historians can view the Timelines section in which information is gathered chronologically, while there's also a dictionary, a built-in notebook for research notes and the option to build and export a report.

The packaging extols the virtues of the product, as you'd expect. For example, we're told that there are some 56 million words of text to be found in the Deluxe Edition that we reviewed (which is supplied on either three CDs or one DVD). There are also more than 11,000 photographs and illustrations and more than 130 video and film clips. For further information you can go to the Britannica Web site and when you register your purchase you get a year's free updates to the program. It's rather like an anti-virus package in this respect, but then history does have a habit of changing on a regular basis...

If you've already got last year's version of this encyclopaedia, or any other that you're happy with, then there's little reason to upgrade. But if you don't have a decent encyclopaedia in your possession, Britannica is definitely worth buying, whether for practical research or just browsing. It's easy to lose yourself in its contents for hours and feed your mind on what's inside. It's far better than sitting in front of any TV documentary, that's for sure.