Definition:

A MAC (Media Access Control) Address is the physical address that uniquely identifies an adapter on a network. An adapter is anything connected to a network which could range from computer to a router or even a gaming platform. A computer's MAC address would be comparable to a person's driver's license. MAC addresses can also be used to restrict access to networks via MAC filters placed on routers.

Details:

MAC addresses contain 12 digits. The first six digits contain the identification number of the adapter manufacturer, and the last six digits represent the serial number assigned to the adapter.


MAC Addresses are not only limited to desktop computers. Laptops and several gaming platforms that are capable of connecting to networks have MAC addresses as well. Mac addresses play an important part in wireless local area networks (WLAN) as well. A MAC address on a LAN connection is comparable to an IP address on the Internet; both serve to identify a device.

Although the main purpose of a MAC address is to permanently identify an adapter with a with a unique code, there are cases of MAC spoofing. MAC spoofing is changing the MAC address of an adapter to bypass access controls, allowing impersonations of other computers.

Related Links:

How Stuff Works: MAC Addresses
About: MAC Addressing