What is a MAC address?

A MAC address (media access control address) is a hardware identifier built into each network interface, such as the Wi-Fi or cable socket of a laptop, written as six pairs of characters like 3C:22:FB:1A:4D:90. Devices on the same local network use it to deliver data to each other. Unlike an IP address, it does not usually change when a device reconnects, so it helps identify a device over time, although modern phones and laptops often use random MAC addresses on Wi-Fi for privacy. Network inventories use MAC addresses, together with device names, to tell devices apart.

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