h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

What about bacteria?

I know it's probably a bit late to reply (I've been out to lunch for some months, but I'm back, baby!!!) but here goes :

In the scheme of things (meaning the things I was writing about in this entry) a bacteria would probably be similar to a worm (the digital kind, not the biological kind).

A worm program stands by itself, and can do damage simply by being executed, whereas a virus is a bit of code that needs a real program to infect, it cannot act while isolated.

If you've ever gotten an .exe file attached to some email and that executable file damaged your system when you tried to open it, you had either a worm, or a virus-infected file.

Trojans (sometimes mistaken for viruses -- virii ? --) are often a kind of worm which tries to pass itself off as a useful application.