Watson wins Jeopardy!

Jeopardy! clues are puns, allusions and misdirection, and answering them in a few seconds was thought to be beyond machines. Over three nights broadcast on 14, 15 and 16 February 2011, IBM's Watson beat Ken Jennings, who had won 74 games in a row, and Brad Rutter, the show's biggest money winner, finishing with $77,147 to their $24,000 and $21,600. Jennings wrote under his final answer: "I, for one, welcome our new computer overlords."

Watson was not a neural network. David Ferrucci's DeepQA system ran hundreds of hand-built analysis modules in parallel over 200 million pages of text, generated candidate answers, scored each with dozens of evidence models, and combined the scores with a learned weighting. It was the last great achievement of the engineered-pipeline approach to language, and it had a buzzer advantage that the human players complained about.

IBM spent the next decade trying to sell Watson to medicine and business, with little success, and sold most of the health division in 2022. The moment on television stood, though: for the public, the test of a thinking machine had shifted from playing chess to answering questions, and the machines that eventually did that were trained rather than built.