Many people in IT think, that data is just 1s and 0s. But in reality we are living in a physical world and as such some form of power is used to transmit those 1s and 0s. This power may is electrical power in terms of voltages with defined generated current or in terms of current with defined voltages (20mA communication heavily seen in industrial equipment). If you have a slow communication link, EMI and other environmental thinks like temperature is not much of an issue. But as faster you like to communicate you need to cope with those things. The electrical contacts in the connectors doesn't help. So people started to put the transceivers into the cables. Those transceivers with additional electronics like ringing suppression circuitry and other "magic" are then best fitted for the desired cables for the desired environments. Then you started to makes those cables smart like to detect the capabilities of the cables like is it really possible to talk at 10Gbps or is it more a cheaper type where 100Mbps is the max. As more smarter those cables get people get creative to put other things in it like "hey, the cable could become a converter as well".