In total, a single fiber-optic cable can carry data at rates as high as 14444 Tb/s. Over short distances, such as networking within a building, fiber saves space in cable ducts because a single fiber can carry much more data than a single electrical cable. Fiber is also immune to electrical interference, which prevents cross-talk between signals in different cables and pickup of environmental noise. Because they are non-electrical, fiber cables can be used in environments where explosive fumes are present, without danger of ignition.

Although fiber optics can be made out of transparent plastic, glass, or a combination of the two, the fibers used in long-distance telecommunications applications are always glass, because of the lower optical attenuation. Both multi-mode and single-mode fibers are used in communications, with multi-mode fiber used mostly for short distances (up to 500 m), and single-mode fiber used for longer distance links. Because of the tighter tolerances required to couple light into and between single-mode fibers; single-mode transmitters, receivers, amplifiers and other components are generally more expensive than multi-mode components.

In 1880, Alexander Graham Bell demonstrated how light could be used to transfer sounds from one area to another. Though it did not work on cloudy days, his discovery did set the stage for fiber optics. In 1930, a German student named Heinrich Lamm demonstrated how fiber optics could be used to examine internal body parts. Since the images were unclear, however, he did not receive a patent for his invention. In 1956, the term "fiber optics" was born when Narinder Kapany coined the term after bundling a few glass rods. He then demonstrated that these rods could project light without leaking at any point, as long as they were wrapped or coated in a dark material. By 1960, Dr. Charles Kao realized the potential of fiber optics. Dr. Kao suggested fiber optics could be used for fast, clear communications. In the 1970's, a company called Corning Glass created the first optical fiber made entirely of thin strands of glass.