The major objective of this article is to know about network interface controller. Network Interface Controller or NIC in small form, is a networking device, used by a computer for announcement during a network. It is the networking element, into which network wire is plugged. This device is also recognized as Network Adapter, Network Interface card and Local Area Network Adapter. It is installed in the host computer to permit the host to be linked to the Local Area Network. Several computers have built in NIC while the others have detachable cards which could be replaced if any require like altering the baud rate or bandwidth arises.