Thursday's victory is significant because it came in a contest of non-linear thinking and natural language questions at which computers have generally lagged far behind their human inventors.

The contest took place at a computer lab at IBM's research headquarters, which was decorated to appear as the set of the long-running US game show, in which the host gives contestants an answer to which they must formulate the question.

The event was a practice for a real live TV contest between two human contestants and the supercomputer named Watson, which is due to air in February with the first placed contestant winning $1 million.

The room-sized computer was represented on the blue set in between the two contestants by a black screen with a glowing globe. The computer correctly answered about half the 15 questions quicker than either of its competitors to claim victory.

The competitors were no duds. One had previously won 74 consecutive matches, while the other had won a record $3.3 million as a contestant on the show.

The milestone is considered analogous to the famous victory of IBM's Deep Blue Computer's victory over World Chess Champion Gary Kasparov in 1996.

IBM said that Watson's victory showed its ability to parse complex questions and sort through tons of data in order to find the relevant answers.

The computer, which is built from 10 racks of IBM servers, has 15 terabytes of RAM and has access to over 200 million pages of content. It did not have the advantage of internet access.

"After four years, our scientific team believes that Watson is ready for this challenge based on its ability to rapidly comprehend what the Jeopardy clue is asking, analyze the information it has access to, come up with precise answers, and develop an accurate confidence in its response," said David Ferrucci, a scientist who leads the IBM Research team that built Watson.