NIC

Also known as a network interface unit (NIU).Traditionally, a device in the form of firmware on a printed circuit board that fits into an expansion slot of a device (e.g., workstation, printer, or server) and provides the necessary programmed logic for that device to interface to a local area network (LAN). Alternatively, multiple cards traditionally were contained within a multiport device that supported multiple devices on a pooled basis. Contemporary computers commonly include NIC functions on the main circuit board, or motherboard. NICs are responsible for medium access control (MAC). Each NIC has a theoretically unique logical MAC address, assigned by the manufacturer, for purposes of identification. See also LAN and MAC.