You can also view previously answered questions in the HSW Question Archive . Answer Over the last 20 years or so, fiber optic lines have taken over and transformed the long distance telephone industry.
Optical fibers are also a huge part of making the Internet available around the world.
When fiber replaces copper for long-distance calls and Internet traffic, it dramatically lowers costs. To understand how a fiber optic cable works, imagine an immensely long drinking straw or flexible plastic pipe. For example, imagine a pipe that is several miles long. Now imagine that the inside surface of the pipe has been coated with a perfect mirror. Now imagine that you are looking into one end of the pipe.