A fiber optic network is made up of cables containing bundles of glass or plastic strands called optical fibers, which carry data that has been transformed into light. The light is transmitted along the fiber optic network by a laser, after having been converted by a computer into digital data signals. Light travels along the cable without “leaking out” by bouncing off the mirror-like walls of the glass or plastic. The structure of the cable also contributes to keeping the light from dispersing. The light beam travels down the core located in the middle of the cable.