If you look at wikipedia definition, a media access control address (MAC address) of a device is a unique identifier assigned to a network interface controller (NIC) for communications at the data link layer of a network segment.
A machine can have multiple MAC addresses, but each NIC as only one MAC address. Packets that are sent on the ethernet are always coming from a MAC address and sent to a MAC address.
How to get MAC address of a Linux machine
You get this output, we highlight below the MAC address “02:9B:B0:CB:AA:FC” of first ethernet adapter “eth0“:
How to get MAC address of a Windows machine
Open a Command Prompt by running “cmd” in “Search Windows” then run:
You’ll get the MAC Address “C0-B6-F9-5B-04-9B” for connected transport: