Select the first letter of the word from the list above to jump to appropriate section of the glossary or type the term on which you want to search.

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Mac

short for Macintosh.

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MAC address

(Media Access Control address) The unique serial number burned into Ethernet and Token Ring adapters that identifies that network card from all others.

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Macintosh computer

a popular home computer introduced in 1984 by Apple. The Mac was the first computer to utilize a graphical user interface (GUI). This operating system uses icons, graphics, pop-up windows and a mouse for easy navigation through its applications. The introduction of the Mac marked the birth of the point and click generation of home computers.

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macro

a key, name, or symbol that represents and initiates a command sequence. For example, for the sake of streamlining repetitive functions, some programs allow you to set your computer to enter your name, address, or any other frequently used phrase or character string, by pressing a particular series of keys. The selected item is then inserted to the chosen location.

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macro virus

a computer virus that is found programmed as a macro, and embedded into a file document. The virus is designed to execute when the document is opened. Today, most viruses are macro viruses. A user can protect his computer by installing and periodically updating antivirus software.

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mail bomb

an email containing a large file or files designed to jam an ISPs server and/or the recipient’s mail program. Once a bomb is opened, depending on the size of the file it contains, it can take hours to load. With many ISPs, a user’s penalty for mail bombing is discontinuation of service.

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mail filter

a program allowing the user to sort email according to its subject or heading.

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mailbox

a directory maintained in an ISP’s server that stores email until a user downloads it. Email may be saved in both the ISPs server or in the users computer.

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maillist

in most modern email programs, the addresses of the people a user sends messages to are stored and called a maillist making it an electronic address book. With this feature a user can also send the same message to everyone on the list with a simple mouse click.

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mainframe computer

a large, stationary computer that requires space in an air conditioned room. Such machines are able to store massive amounts of data, support many users simultaneously, and run a wide variety of applications all at one time. Before home computers became available in the early 1980s, mainframes were the only computers. They were used by governments worldwide and large corporations. IBM and Unisys are the leading manufacturers of mainframe computers.