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For communications, optical fiber has significant advantages over copper wire. Both methods are electromagnetic waveguides. In the case of copper wires, the electromagnetic waves are guided between two conductors -- a pair of wires; whereas in an optical fiber, the waves are light, guided by the internal structure of the glass fiber. Optical fiber is immune to electromagnetic interference; leakage of signal from one fiber to another is much less of a problem than cross-talk between electrical waveguides; optical fiber can be made to have less attenuation than copper. These advantages allow the pulses of light to be switched on and off much higher than the pulses of electricity in wires, so that more information can be sent per second.  

For communications, optical fiber has significant advantages over copper wire. Both methods are electromagnetic waveguides. In the case of copper wires, the electromagnetic waves are guided between two conductors -- a pair of wires; whereas in an optical fiber, the waves are light, guided by the internal structure of the glass fiber. Optical fiber is immune to electromagnetic interference; leakage of signal from one fiber to another is much less of a problem than cross-talk between electrical waveguides; optical fiber can be made to have less attenuation than copper. These advantages allow the pulses of light to be switched on and off much higher than the pulses of electricity in wires, so that more information can be sent per second.  

== References ==

== References ==