A MAC (Media Access Control) address is a unique physical address assigned to network interfaces for communication on the physical network segment. It is used for direct data exchange within a network, ensuring that data packets are delivered to the correct device. Unlike IP addresses, MAC addresses operate at the data link layer (Layer 2) of the OSI model and are hard-coded into the network interface card (NIC) by the manufacturer. References: Axis Communications networking guides and standard networking principles.