Kasparov, playing white, made his first move (Pawn to E-4) at a park in New York, watched by crowds of reporters and chess fans.
Now it is up to a team of young chess experts to enter suggested moves for Internet participants to consider for 24 hours.
The move with the most votes will be played and the game will continue until one side resigns.
![[ image: width=150]](/olmedia/370000/images/_374653_kasparov150.jpg)
"I'm inviting everyone from all over the world with the slightest interest in chess to play me," said the Russian grandmaster.
"I expect this to be a high-quality match and most probably at some point I will have to come up with some kind of novelty move in order to win."
The game will be hosted on the MSN Gaming Zone site and they predicted hundreds of thousands of participants. Millions of Net users are believed to have followed Mr Kasparov's matches against IBM's chess-playing computer, Deep Blue.
Help allowed
The rules for the game allow 24 hours for each side to move. They will also allow the playing public to make use of chess computer programs.
Mr Kasparov says this computer assistance will eliminate the potential for a serious mistake by his opponents.
"I don't think the world will decide to do something dramatic, or something stupid," he said. "Not only because of the recommendation of the experts, but also most will have computers and the machine will prevent even amateurs from making mistakes."
The four young experts heading the team against Kasparov are grandmaster Etienne Bacrot, 16, from France; American Florin Felecan, 19; US women's chess champion Irina Krush, 15; and German Elisabeth Pahtz, 14.
Computer challenge
Mr Kasparov is widely regarded as the greatest chess player ever. He has been particularly strong over the last few months with three convincing tournament victories in a row.
In 1996 and 1997, he played two six-game matches against the Deep Blue, winning the first and losing the second.
It was the first time a computer had defeated a reigning world champion in a match played under classical chess rules. The chances of the world beating Mr Kasparov seem lower.
Giving chess a sporting chance
(16 Mar 99 | Sport)
Kasparov vs the World
Kasparov vs Deep Blue
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