Optical fibre cable, containing a bundle of optical fibres conducting light. These fibres are made of very pure glass which is coated so as to allow light to be transmitted without absorption or loss of intensity. Optical cables transfer data at the speed of light in glass.This allows data such as telephone conversations, television pictures and computer transmissions to be sent in large volumes without a loss of quality. Modern fiber cables can contain up to a thousand fibers in a single cable, with potential bandwidth in the terabytes per second.