Carbon fibres consist of a long chain of carbon atoms. They are stronger than steel and possess a very high tensile strength even at higher temperatures. They are also corrosion resistant. They are used for making components of aircrafts, body of autombiles, sports goods like shoes and tennis racquets, artificial implants for the body, etc.
Optical fibres are fine thread-like tubes made of glass. They can carry information coded in light or infrared signals. It is used in tele-communication, in performing surgery of internal organs without cutting open the body.