Parametron: 50s Japanese computer that uses neither transistors nor vacuum tubes

The Parametron was a groundbreaking 1954 Japanese computing technology invented by Eiichi Goto that used ferrite cores instead of transistors or vacuum tubes to create logic circuits. The technology was used to build the PC-1 Parametron Computer, which was widely adopted for scientific research and training, and spawned multiple commercial variants from major Japanese electronics manufacturers. The Parametron represented a significant technological achievement that influenced early computer development and helped nurture a new generation of computer engineers in Japan.