I've really enjoyed this year's Royal Institution Christmas Lecture series -- 'Hi-tech Trek: The Quest for the Ultimate Computer', given by Prof. Chris Bishop. For readers outside the UK, this is an annual lecture series on some aspect of science, primarily intended for children. I've watched some of the lectures in other years, and they are sometimes a bit patchy. However, I thought that Chris Bishop did a fantastic job of explaining quite difficult concepts, accompanied by the requisite number of explosions, feats of dare-devilry and maths problems disguised as magic tricks, and yet he avoided the trap of patronising the audience.

As a lecturer myself (though at nothing like such an exalted level), I find it interesting watching other people give lectures, and I often hope to pick up some tips and tricks. The basis of every good lecture -- regardless of subject or the academic level of the audience -- is telling a compelling story. A true story of course, but if you don't engage the audience, you might as well be talking to yourself. I often think that what you're trying to do is to gently guide your audience so that they just about get to each point just before you do. If -- as an audience member -- you're not trying to answer the questions posed by the lecturer before they tell you what the answer is, they've lost you.

I think that this lecture series succeeded so well because Chris Bishop told a great story, and there was something for everything. Mr. Bsag has less knowledge of Computer Science than me (and less interest in it), but we both learned some new and interesting things. For example, I was astonished that the chip in a chip-and-PIN credit card has roughly 30 times the processing power and 100 times the memory of the landing guidance computer on board the Apollo 11 Lunar Module. What I find surprising is not how powerful chip-and-PIN chips are, but that they actually managed to land the module on the moon with such meagre computing resources. I know that it's a factoid, but it does bring home to you just how quickly computing power has increased.

I do wish that my undergraduates were as keen to participate, though: a great forest of arms went up each time he asked for a volunteer, and the helpers looked really chuffed with their role of pouring small yellow balls into a tank, or standing in front of a 3D camera. In one of the lectures, each audience member had a gift-wrapped pair of transparent polarising films. Bishop demonstrated how the light was alternately blocked and transmitted by the films as they were overlaid and one rotated 90#176; relative to the other. Judging by the gasps of delighted astonishment coming from the kids (and the fact that you could see them still playing with the films for the rest of the lecture), I think that their parents had probably wasted their money on Playstations and Wiis for Christmas.