In his otherwise intriguing book, Digital Fortress ($7.99 in paperback from Amazon US), author Dan Brown makes several schoolboy errors. For instance, top of page 69 he says that, “Computer viruses were as varied as bacterial viruses…”
I doubt he is referring to bacteriophages here and is simply making the mistake that bacteria and viruses are essentially one and the same, i.e. germs! That aside, computer viruses are by no real measure as varied as biological viruses. There are, of course literally tens of thousands of computer viruses and worms, but essentially they are all variants of a few hundred that exist “in the wild”. In contrast, there is at least one virus for every species on earth…and that’s almost beyond counting.