Three-state logic

Three-state logic is a type of logic that takes three values instead of two values like regular logic. The three values are 1 (or true), 0 (or false) and a third value called the ‘high impedance’ state. In this high impedance state, the logic is not responding and the output is in an undefined state. This can be useful in situations like when you want to connect two wires together, but don’t want any current to actually flow between them. The high impedance state makes sure no current is flowing.