CNet delves into the history of the emoticon. From the article:
The origin of the ASCII smiley face is typically traced to September 1982, when Scott Fahlman, a research professor at Carnegie Mellon University's Department of Computer Science, suggested that the :-) symbol be used in the subject line of an online bulletin board post to denote a humorous or non-serious topic.More at the link.
"Nobody ever guessed that this would catch on. I certainly didn't," said Fahlman, who is still on the faculty at Carnegie Mellon. But as he recounted, the trend spread, initially to other Internet-pioneering universities like Stanford University and the Massachusetts Institute of Technology, and then beyond.
"As the Internet grew, it escaped this little closed community of computer scientists and made it into first other universities, a much larger group, and then out into the general public," Fahlman said. "It's been interesting to see (smiley faces) trickle from place to place, and now it's showing up in postings from Russia and China and all over the world. It's been fun to watch that."