NIC

A NIC - or Network Interface Card - is a computer expansion card that allows the connectivity of all of the computers in a network. They are sometimes, however, built into the computer. NICs are typically used to join together computers to form a LAN.

Each device - or node - that is attached to a network comminicates with each other within that network. It is the job of the Network Interface Card to analyze and transmit that data to the correct node.