Fiber-optic communication is a form of optical communication for transmitting information from one place to another by sending pulses of infrared or visible light through an optical fiber. The light is a form of carrier wave that is modulated to carry information. Optical fibre is preferred over electrical cabling for long-distance transmission. In telecommunications, fiber optic technology has virtually replaced copper wire in long-distance telephone lines, and it is used to link computers within local area networks. Fiber optics is also the basis of the fiberscopes used in examining internal parts of the body (endoscopy) or inspecting. Fibers commonly used in optical communication are single mode and GI. Information capacity determination, Group.