Garry Kimovich Kasparov (Russian: Га́рри Ки́мович Каспа́ров, Russian pronunciation: ; born Baku,Azerbaijan Garry Kimovich Weinstein, 13 April 1963) is a Russian (formerly Soviet) chess grandmaster, a former World Chess Champion, writer, and political activist, whom many consider the greatest chess player of all time.
Kasparov became the youngest ever undisputed World Chess Champion in 1985 at the age of 22. He held the official FIDE world title until 1993, when a dispute with FIDE led him to set up a rival organization, the Professional Chess Association. He continued to hold the "Classical" World Chess Championship until his defeat by Vladimir Kramnik in 2000. He is also widely known for being the first world chess champion to lose a match to a computer, when he lost to Deep Blue in 1997.
Kasparov's ratings achievements include being rated world #1 according to Elo rating almost continuously from 1986 until his retirement in 2005 and holding the all-time highest rating of 2851. He was the world number-one ranked player for 255 months, by far the most of all-time and nearly three times as long as his closest rival, Anatoly Karpov. He also holds records for consecutive tournament victories and Chess Oscars.