A Media Access Control (MAC) address is a unique identifier assigned to a network interface controller (NIC) for communication on a physical network segment.
It is a 48-bit address that is written in the format of 12 hexadecimal digits, separated by colons (e.g. 00:11:22:33:44:55).
A MAC address is used by the Media Access Control protocol in the Data Link Layer of the OSI model, to identify a device on the network. It is used to determine the source and destination of data packets on a LAN (Local Area Network) or WAN (Wide Area Network).
An example of a MAC address would be 00:0A:95:9D:68:16, this would be the unique identifier of a network interface on a device.
The first 24 bits represent the manufacturer's unique identifier. the remaining 24 bits represent the NIC's unique identifier.
MAC addresses are used by the data link layer (layer 2) of the OSI model to identify and address devices on a network, and are typically hard-coded into the NIC's firmware by the manufacturer. They are also used for filtering and forwarding data packets at the MAC layer, and for troubleshooting and monitoring network devices.