Copper Wire

                         =>   The most common medium as its is

                                =>  inexpensive and easy to install

                                      Why copper?

                                => The biggest problem is interference which

                                     results in noise

                                =>  At its worst when wires run parallel and

                                      close together

 Solution 1: twisted pair                          Solution 2: coaxial cable

 |    Shield the wires and then twist     |  Single wire surrounded by cylindrical

       them gather (e.g., telephone wires)          metal shield

     |  Minimizes both radiation and        | Shielded twisted pair may be used if     

             susceptibility o radiation                     Wires  Pass through strong

                                                                 electromagnetic  fields