Source : Free On-Line Dictionary of Computing

RG58
     
         A common, low-impedance (52 ohm), quarter-inch
        diameter {coaxial cable} used for {10base2} {Ethernet} wiring,
        sometimes called "{cheapernet}" in comparison with "full spec"
        {RG8} cabling.  A member of the "Radio Guide" series.
     
        (2002-06-17)