A high-speed data transmission medium containing glass or plastic threads that carry light beams. Digital data is transmitted through the cable via rapid pulses of light. Because fibre-optic cables provide high bandwidth, they are used for a large part of the Internet backbone. Most transatlantic telecommunications cables between the U.S. and Europe are fibre optic. In recent years, fibre optic technology has been deployed for regional and local Internet connections. These connect major regions of the world to each other. Maps: http://www.submarinecablemap.com and http://www.internetexchangemap.com.