Network interfaces are hardware or virtual components that allow a system to connect to a network. These interfaces can be physical, such as Ethernet or wireless adapters, or virtual, such as loopback interfaces(l0).
Each network interface has a unique name, such as eth0 or wlan0, and is identified by a unique MAC (Media Access Control) address. The MAC address is a unique identifier assigned to each network interface by the manufacturer.
Linux supports many different types of network interfaces, including wired Ethernet, wireless (Wi-Fi), Bluetooth, 3G/4G cellular modems, and virtual interfaces such as the loopback interface (lo). Network interfaces can be configured with IP addresses, netmasks, and other networking parameters to enable communication with other devices on a network.
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