By the late 1980s, the top chess computers, Hitech and ChipTest, were able to run their searches deep enough and fast enough to beat top chess GMs. The chess world was stunned in 1989 when the unthinkable finally happened.
Hitech beat GM Arnold Denker and Chiptest's machine, Deep Thought beat serial World Championship Candidate GM Bent Larsen. Man vs Computer events were held regularly during the 90s with teams of top human players defending humanity's honor against the machines. The humans were winning at first. However slowly but surely the pendulum swung towards the computers.
The big question on everyone's lips was if or when a computer would or could ever win a match against a reigning World Champion. Kasparov smashed Deep Thought
+3-1=2 in Philidelphia in 1996. A year later, Deep Thought, since renamed Deep Blue, turned the tables on Kasparov, winning
+2-1=3 in New York. This was the biggest event to date in the history of computer chess.