What is a MAC address?

Media Access Control address (MAC address) is a hardware identifier of a network device (network card, Wi-Fi adapter), unique for each instance within a local network. It consists of 6 groups of two hexadecimal digits, separated by colons or hyphens. For example, 00:1A:2B:3C:4D:5E. The first part (the first 3 groups) identifies the manufacturer, the second — the device's serial number. The MAC address is used at the data link layer of the OSI model for routing data within a local network segment. It is not used for routing in the global network (Internet).