When I was young, my parents bought a 20-volume encyclopedia, mostly justifying it because it would be a valuable asset in my education. Like all encyclopedias, it had its limitations, but it was very good if you just wanted to find out a fact-in fact one volume even had a sort of ‘fact book’ in it. But it was bulky, expensive and slow to use. Today, the CD ROM has made encyclopaedias much more accessible. If you need a particular piece of information, a CD ROM encyclopedia is probably the best starting point. It’s immediately available (well, as soon as your PC has started up) and is very quick and easy to search.