What Is a Network Interface Controller (NIC)?

A network interface controller (NIC) is a piece of hardware (typically a circuit board or chip) that connects a computer to a network. You set up a NIC inside the device, and it provides a physical connection to a network via a cable (such as Ethernet).

Modern NICs provide extra functionality to computers in addition to basic networking, such as support for DMA interfaces, partitioning, I/O interrupts, and network traffic engineering. Other common names for a NIC are a network interface card, network adapter, and physical network interface.