Digital circuits are electric circuits determined by quite a few discrete voltage levels. Digital circuits would be the most typical physical representation of Boolean algebra and would be the basis of all digital computers. To most engineers, the terms digital circuit, digital method and logic are interchangeable within the context of digital circuits. Most digital circuits use a binary method with two voltage levels labeled 0 and 1. Frequently logic 0 will be a reduced voltage and known as Low even though logic 1 is known as Higher. Even so, some systems use the reverse definition (0 is Higher) or are current primarily based. Ternary (with 3 states) logic has been studied, and some prototype computers produced. Computer systems, electronic clocks, and programmable logic controllers are constructed of digital circuits. Digital signal processors are one more instance.