Going into the deciding game, the opponents were tied with one win apiece and three draws. Kasparov was tired, "not in the mood of playing," as he put it. Deep Blue, as always, was implacable, humorless, inexorable -- and invincible.

It didn't take Kasparov long to get his wires crossed. In his seventh move, he started to transpose two steps in a well-known defensive maneuver. Against a lesser opponent, he might have recovered from his blunder. But Deep Blue, missing nothing, immediately took advantage of the situation and killed Kasparov's strongest piece -- his queen.

Off the deep end
Here's the cruel part: What was widely and correctly seen as a huge victory for computers came down to a single -- and highly uncharacteristic -- human mistake. Kasparov "has never been known to make such a mistake in his entire chess career," said grandmaster Daniel King, commenting during the game on Kasparov's home site.

If you haven't played, chess is an unforgiving game. The sequence of moves can be vital. Reversing them -- as Kasparov did -- can be as fatal as diving into a swimming pool, and then filling the pool.

And it didn't take long for Kasparov to start looking like a man who had dived into an empty swimming pool. After just 19 moves, he conceded defeat and lost the match 3-1/2 to 2-1/2.

For its long effort to develop Deep Blue, IBM enjoyed a PR feeding frenzy, picked up a $700,000 prize, saw its stock price rise, and even earned praise from arch-rival Microsoft. The match was also an Internet occasion, where the games were broadcast, move by move, at an IBM site. (FWIW, The Why Files admits that when we surfed over to the 64-squares slug-fest, we were distinctly underwhelmed by the Java programming.)

Kasparov, meanwhile, put on a display of dismayed bad sportsmanship and moved off stage to salve his wounds with the $400,000 loser's purse. He intimated that the computer had had some kind of human assistance and talked darkly about "mysteries."

We doubt that. But more impressive is Kasparov's constant complaint that the match was imbalanced: While the Deep Blue team could study all of Kasparov's matches, he saw none of his opponent's games. (If that sounds trivial, know that grandmasters routinely train by examining opponent's games.)

No longer science fiction
Still, the world champion now faces the possibility of seeing an embarrassing asterisk next to his name: Garry Kasparov * world champion.

At any rate, the implications of the match went far beyond money and chess. The victory was the culmination of a 50-year battle between enthusiasts of artificial intelligence (AI) and human chess players. "It's terrific," says David Waltz, vice-president of the NEC Research Institute in New Jersey and president-elect of the American Association for Artificial Intelligence. "AI has been criticized over the years for making grandiose claims that it has failed to deliver. It's clear that this is a milestone."

Even more important, the match symbolized the growing power of machines. Remember when talking machines, smart robots, and autonomous vehicles were considered science fiction? Now all exist in reality.