Fiber-optic cables, which run underground, above ground, and under the ocean, form the larger “backbone” fiber-optic network.
These cables (not to be confused with traditional copper cables used in DSL connections) are made up of bundles of thousands of tiny glass strands or fibers. Each fiber is extremely tiny — almost as thin as a strand of human hair. The optical fibers transmit light, which carries data the length of the cable at incredibly high speeds.
There are two essential components of a fiber-optic cable: the “core” and the “cladding.”