(The network card is ultimately connected to the network, so there must be an interface through which the network cable can be connected to other computer network devices. Different network interfaces are suitable for different network types. Nowadays, common interfaces mainly include RJ-45 interface of Ethernet, BNC interface of thin coaxial cable, AUI interface of thick coaxial cable, FDDI interface, ATM interface, etc. And some NICs provide two or more NICs for a wider range of use environments.)