Even a billion moves a second... ...is not enough to beat a human

The pinnacle of man's technological endeavour is still no match for the human brain. At least not for the brain of Garry Kasparov, who defeated Deep Blue - the 256-processor, IBM super-computer - by four games to two, in a $500,000 challenge match.

After a difficult start to the contest in Philadelphia, Kasparov seemed suddenly to crack the problem of finding a style of chess guaranteed to bamboozle this awesome machine. In the first game of the match, Deep Blue had shown that it was capable of out- calculating the strongest human player.

Perhaps it just took him by surprise. But then Kasparov displayed a tactical flair far beyond anything mere microchips can muster, eventually levelling the match to two-all and then taking the fifth, after Deep Blue's determined programmers rejected a draw.

The final game was an even more striking display of human intelligence. An ill-advised excursion by Deep Blue in the opening resulted in a loss of precious time.

Unable to break out of a passive position, it simply moved its pieces sideways and backwards while Kasparov's forces edged inexorably forwards. And forwards.

After the stunning opening win - the first time a computer had beaten a world champion in serious play - Deep Blue's programmers must now go back to the drawing board.

Deep Blue seizure, Section Two, page 22