In Star Trek: The Original Series, the Enterprise's M-5 computer system is associated with duotronics.
Duotronics is a fictional computer technology developed in the Star Trek universe to describe highly advanced electronic processing. The concept is especially prominent in “The Ultimate Computer,” where Richard Daystrom designs the M-5 multitronic computer and installs it aboard the USS Enterprise.
The term is often confused with multitronics. Duotronics is the earlier technology associated with starship computers, while multitronics describes the more advanced M-5 architecture. The episode presents M-5 as a major step toward automating a starship, although its failure demonstrates the danger of giving a computer too much authority over weapons and navigation.
Star Trek later used different computer concepts, including isolinear optical chips and bio-neural circuitry. These technologies belong to later eras and are not alternate names for duotronics.