What is a fiber-optic cable primarily composed of?

A fiber-optic cable is primarily composed of small strands of glass. These glass fibers are capable of transmitting data in the form of light signals, which allows for high-speed data communication over long distances with minimal loss of quality. The glass fibers are surrounded by a protective coating and a layer of insulating materials that help maintain the integrity of the fibers and facilitate effective data transmission.

The properties of glass enable it to have a high refractive index, meaning that the light signals can be guided effectively along the fiber, avoiding loss of signal strength that can often occur in electrical cables. This design is what makes fiber-optic cables favorable for telecommunication networks, internet connectivity, and other data-intensive applications, distinguishing them from other types of cables that are composed of metals, plastics, or carbon fibers.