ARP stands for Address Resolution Protocol. It is a protocol used to map a network address, such as an IP address, to a physical (MAC) address on a local network. For instance, When a device on a network wants to communicate with another device, it needs to know the other device’s MAC address. ARP allows a device to send a broadcast message to all devices on the network, asking for the MAC address associated with a specific IP address. The device with that IP address will respond with its MAC address, and the first device can then send its data directly to the second device.
ARP is used by IP, which is a network layer protocol, to map a network address (IP address) to a link layer address (MAC address). It is a critical component of IP networking and is used to resolve the MAC address of a device when its IP address is known.