A thin glass through light can be transmitted.
Optical fibers (Fiber optics) are long, thin strands of very pure glass about the diameter of a human hair. They are arranged In a bundles called optical cables and used to transmit light signals over long distances.

Main applications of Optical fibers are communication system, medicine, sensors, military, and electronics.

(1) In medical field fiber optics provide a very compact, flexible conduit for light or data delivery in equipment, surgical, and instrumentation applications.

(2) Telecommunications used as fiber optics is laid and used for transmitting and receiving purpose.

(3) Military or government used as hydrophones for seismic and SONAR uses, as wiring in aircraft, submarines and other vehicles and also for field networking.