CAT3 and CAT5 wire are types of unshielded twisted pair wiring. Both types have 4 pairs of twisted wires that rely on the twisting to prevent noise. Category 3 wire is not used as much today but is much cheaper than Category 5. Category 3 can only handle a maximum of 10Mbps at 16MHz compared to Category 5 being able to handle 100Mbps at 100MHz. Most people use the faster Category 5 for networking since it can handle faster speeds. Category 3 wiring is mainly used for telephone services that use multiple lines. Writer Bio
