What Does Optical Fiber Mean?
An optical fiber is a flexible, transparent strand of very pure glass that acts as a light pipe to transmit light between two ends of the fiber. Optical fibers have a core surrounded by a cladding layer made of dielectric material. The optical signals in the core are confined by establishing a refractive index that is greater than the cladding.
Techopedia Explains Optical Fiber
Optical fibers is used as a medium for telecommunication and networking. Light in a fiber optic cable travels through a core by constantly bouncing from the cladding, a principle termed total internal reflection. As the cladding does not absorb any light from the core, light waves travel longer distances. Fibers with a sizable core diameter may be analyzed by geometrical optics. These fibers are called multi-mode fiber.