What is a mac address?

Broadly speaking, a MAC address (media access control address) is a unique identifier assigned to most network adapters or network interface cards (NICs). It acts as a form of personal identification that enables data packets to be routed around the world, allowing any two computers to communicate with each other.

A MAC address is a combination of six groups of two hexadecimal digits that are typically represented in either one of two ways -- with or without separation characters like colons or dashes. Some common examples of conventional MAC addresses include 00:11:22:33:44:55 and 35-9E-0E-45-CB-1B.

The purpose of MAC addresses is threefold. The first is to allow for transfers involving broadcast traffic, like ARP broadcasts that are necessary for routing packets through networks. The second is toallow for transfer across layer two boundaries, like between switches and routers in the same subnet. Lastly, the MAC address ensures that all machines on the same local area network can easily be identified.

A key point about MAC addresses is that they are unique on an individual device basis and not by 'brand' or 'model'; meaning all Macbook Pros have different MAC addresses, despite being the same model. Also, because a device's MAC address can easily be obtained by monitoring network traffic; they should never be used as a security mechanism but rather as a means of identifying devices in order to facilitate communication between machines or networks.

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