Refraction of light — Describe

How are optical fibres used, particularly in telecommunications?

Optical fibres are thin, flexible strands of glass or plastic that carry light (or infrared) signals along their length by repeated total internal reflection off the sides of the fibre. In telecommunications, information such as sound, video and data is converted into digital pulses of light and transmitted along fibre-optic cables, allowing large amounts of data to be sent quickly over long distances with very little signal loss.