what is a nic

A NIC (network interface card), also known as a network interface controller, network adapter, LAN adapter, or physical network interface, is a computer hardware component that connects a computer to a computer network. It is typically a circuit board or chip that is installed on a computer to provide a dedicated network connection to the computer. A NIC allows computers to communicate over a computer network, either by using cables or wirelessly. It provides physical access to a networking medium and, for IEEE 802 and similar networks, provides a low-level addressing system through the use of MAC addresses that are uniquely assigned to network interfaces. Each communicating device (node) on a LAN must have at least one NIC card. Modern NICs provide functionality to computers, such as support for I/O interrupt, direct memory access (DMA) interfaces, data transmission, network traffic engineering, and partitioning.