A fiber-optic cable, also known as an optical-fiber cable, is an assembly similar to an electrical cable but containing one or more optical fibers that are used to carry light. A TOSLINK optical fiber cable with a clear jacket. These cables are used mainly for digital audio connections between devices. With. Unlike copper wires, which are limited by lower data transmission speeds, shorter transmission distances, and higher susceptibility to electromagnetic interference, fiber optic cables offer unparalleled performance and can cover much greater distances without bumping up against signal degradation. Optical fiber is a technology used to transmit data by sending short light pulses along a long fiber, which is typically made of glass or plastic.