trinary
Trinary logic is three-level digital logic, with states represented by the numbers -1, 0, and 1. Alternatively, the three states can be represented by the numbers 0, 1, and 2. The smallest number corresponds to logical falsity, the highest number to logical truth, and the middle value to logical neutrality (neither truth nor falsity). Trinary logic is not often used. Binary logic, in which there are only two states represented by 0 and 1, is the most common in computer science and electronics.

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