Your MAC (Media Access Control) address is a identifier for physical number network adapters installed on your computer, like IEEE 802, and Ethernet assigned in the network interface cards (NICs) by manufacturer for identification.
To find your MAC address for windows just Open cmd.exe > Go to Start > Search programs and files or run > type cmd click enter or > click open cmd.exe at the results > type ipconfig /all. Your MAC address will be the physical address under Ethernet adapter local area connection.
To find your MAC address for you Linux system use su to become root. Type ipconfig -a and eth0 results will have a HWaddr. The number next to HWaddr is your MAC address.