Stands for "Media Access Control Address," and no, it is not related Macintosh computers. A MAC address is a hardware identification number that uniquely identifies each device on a network. The MAC address is manufactured into every network card, such as an Ethernet card or Wi-Fi card, and therefore cannot be changed. Because there are millions of net workable devices in existence, and each device needs to have a unique MAC address, there must be a very wide range of possible addresses. 

For this reason, MAC addresses are made up of six two-digit hexadecimal numbers, separated by colons. For example, an Ethernet card may have a MAC address of 0C:60:76:3B:CE:67. Fortunately, you do not need to know this address, since it is automatically recognized by most networks.

::IF YOU WANT TO FIND THE ADDRESS::

Windows:

* Open Command prompt ( Start ---> RUN ---> cmd )

* Type ipconfig/all

* The physical address is your mac address.

MAC:

* From the Apple menu, select System Preferences. 

* Select Network.

* From the sidebar, select a network interface, such as Wi-Fi. (Remember, every network interface has a different MAC address.) 

* Click Advanced. Select the Hardware tab. The window shown below appears.

The MAC address for the selected network interface is displayed in the window. 

::IMPORTANT:: MAC ID for LAN & W-LAN are different

You should not share your MAC address with anyone except authorized IT personnel. MAC addresses are unique and permanent, but they can also be spoofed by attackers. In a worst-case scenario, a malicious individual could acquire and spoof your MAC address, and you could be blamed for the illegal activity conducted by the malicious individual. So please, protect your MAC addresses!