Which IBM chess computer defeated Garry Kasparov in a 1997 match?

Which IBM chess computer defeated Garry Kasparov in a 1997 match? Deep Blue defeated him in the 1997 rematch.

IBM’s machine was a customized RS/6000 SP supercomputer, developed from earlier systems called ChipTest and Deep Thought. The name Deep Blue was also a play on IBM’s nickname, “Big Blue.” Computer scientist Feng-hsiung Hsu helped lead its development, with Murray Campbell and other IBM researchers.

Deep Blue first faced Kasparov in 1996 and lost that six-game match 4–2, although it became the first computer to win an individual game against a reigning world champion under standard tournament conditions. After a major hardware upgrade, it returned in May 1997 and won the rematch 3½–2½.

A common mix-up is confusing Deep Blue with IBM Watson, which became famous for answering natural-language questions on Jeopardy! Watson was not the chess computer. Deep Blue was dismantled after the historic match, so no official rematch took place.