Mr. Berliner, playing Black, essayed the Two Knights Defense, one of the more complicated openings. Mr. Berliner was also an accomplished over-the-board player. There were about 60 possible moves at any one time and 21 possible results from the roll of the dice. It quickly ascended to the rank of master and then to senior master, becoming the world’s strongest chess computer. In an email, Mr. Ebeling recalled Mr. Berliner as demanding but fair.

Source: New York Times January 17, 2017 00:52 UTC