A MAC address (Media Access Control address) is a unique identifier assigned to a network interface controller (NIC) for use as a communication address in a network. It is a 48-bit number that is typically written in hexadecimal format as 12 hexadecimal digits, for example, 00:11:22:33:44:55.
MAC addresses are used to identify devices on a network and to control access to network resources. They are also used to track the movement of devices on a network and to troubleshoot network problems.