It's ironic, really. Computer networks bring people together who'd otherwise never meet. But the impersonality of the medium changes that meeting to something less -- well, less personal. Humans exchanging email often behave the way some people behind the wheel of a car do: They curse at other drivers, make obscene gestures, and generally behave like savages. Most of them would never act that way at work or at home. But the interposition of the machine seems to make it acceptable.

The message of Netiquette is that it's not acceptable. Yes, use your network connections to express yourself freely, explore strange new worlds, and boldly go where you've never gone before. But remember the Prime Directive of Netiquette: Those are real people out there.

Would you say it to the person's face?

Writer and Macintosh evangelist Guy Kawasaki tells a story about getting email from some fellow he's never met. Online, this fellow tells Guy that he's a bad writer with nothing interesting to say.

Unbelievably rude? Yes, but unfortunately, it happens all the time in cyberspace.

Maybe it's the awesome power of being able to send mail directly to a well-known writer like Guy. Maybe it's the fact that you can't see his face crumple in misery as he reads your cruel words. Whatever the reason, it's incredibly common.

Guy proposes a useful test for anything you're about to post or mail: Ask yourself, "Would I say this to the person's face?" If the answer is no, rewrite and reread. Repeat the process till you feel sure that you'd feel as comfortable saying these words to the live person as you do sending them through cyberspace.

Of course, it's possible that you'd feel great about saying something extremely rude to the person's face. In that case, Netiquette can't help you. Go get a copy of Miss Manners' Guide to Excruciatingly Correct Behavior.