In technology terms, MAC or Mac can refer to one of three common definitions:
(1) An acronym for Media Access Control, MAC is a network sublayer that controls transmission hardware. The MAC sublayer works with the Logical Link Control (LLC) sublayer to create the Data Link Layer (also called Layer 2) of the Open Systems Interconnection (OSI) model. This layer is responsible for moving data packets to and from one Network Interface Card (NIC) to another across a shared channel. In this context, MAC may also refer to the frame structure that houses MAC addresses, which are used to identify each node of a network.
(2) Mac refers to the brand name and registered trademark for a line of laptop and desktop computers from Apple, Inc. The Mac was initially launched in 1984 as the Macintosh, the first personal computer to have a graphical user interface (GUI), 3.5″ floppy disk drive, and consistent operating system. Since then, the family of Mac computers has been expanded to include the MacBook Air, MacBook Pro, iMac, iMac Pro, Mac Mini, and Mac Pro.
(3) MAC is also an acronym for Mandatory Access Control, a type of access control that gives an administrator complete authority over usage and access policies for other users. MAC is the opposite of Discretionary Access Control (DAC), which gives complete control to the individual user.