I'm considering sending my 17 year old to Carnegie Mellon for a degree in computer science, and what better recommendation could there be than the following?:
On Sept 19, 1982, Scott Fahlman, now a professor at CMU, invented the emoticon (i.e. emotional icon) via a newsgroup posting, starting the ball rolliing with :-) which means "that's a joke, or happy" and :-( which means the opposite. By now you've all seen these. They actually do a good job of alerting people to sarcasm in print, which typically doesn't work well except in the hands of exceptional writers (who are often snobby about the use of emoticons).
Now the concept has evolved into a plethora of new additions: