A Network Interface Card (NIC) is a hardware component that allows computers and other devices to connect to a network. It can be wired, using an Ethernet cable, or wireless, using Wi-Fi technology. The NIC converts data from the computer into a format suitable for transmission over the network and vice versa. NICs are essential for enabling communication between devices, such as connecting a computer to the internet or a local area network (LAN). They often come built into the motherboard but can also be added as expansion cards for enhanced performance or additional features.