Categories 1 through 6 are based on the EIA/TIA-568-B standards. Most new wiring for LANs is CAT5e, an improved version of CAT5. See twisted pair.

                        Application
 Category               MHz=bandwidth
        Cable type      Mbps/Gbps=maximum data rate

 CAT1   UTP             Analog voice
 CAT2   UTP             Digital voice up to 1 Mbps

 CAT3   UTP, ScTP, STP   16 MHz,  4 Mbps
 CAT4   UTP, ScTP, STP   20 MHz, 16 Mbps

 CAT5   UTP, ScTP, STP  100 MHz,  1 Gbps
 CAT5e  UTP, ScTP, STP  100 MHz,  1 Gbps
 CAT6   UTP, ScTP, STP  250 MHz, 10 Gbps/55 meters
 CAT6a  UTP, ScTP, STP  500 MHz, 10 Gbps/100 meters
 CAT7   ScTP, STP       600 MHz, 10 Gbps/100 meters