Single Mode fibers have a smaller core, allowing light to travel in a single, straight path, ideal for long distances with less signal loss. TOSLINK – Optical Audio. There are two main types of fiber optic cables: single mode and multimode. Although they can do the same job in some instances, the different construction methods make each of them better suited to certain tasks and budgets. That makes picking between single mode and multimode fiber optic cables an. Optical fibers are among the most transformative technologies in modern photonics, quietly enabling the global internet, precision sensing, minimally invasive medicine, and high-power industrial laser systems. At their core, all optical fibers perform the same fundamental task – guiding light. But not all fiber cables are created equal: multimode (MM) and single mode (SM) fibers are the two primary types, each engineered for specific use cases, from short-range data center connections to transcontinental telecom backbones.