Glossary of Computer Terms—M

Glossary of Computer Terms—M

M

MACHINE LANGUAGE: Sets of numeric binary code instructions in a computer which execute its operations. All other programming languages (SOURCE PROGRAMS) must be translated into machine language (OBJECT PROGRAM) before entering the CPU.

MACRO: A combination of commands, instructions, or keystrokes which may be stored in a computer’s memory to be executed as a single command by a single keystroke or a simultaneous combination of keystrokes.

MACROASSEMBLER: An assembly language translator that converts macro expressions into several machine language instructions. Although macros simplify program coding and speed up execution of a program, a code for each macro must also be generated.

MAC OS: An operating system with a graphical user interface, developed by Apple? for Macintosh? computers. Current System “X.1” (10) combines the traditional Mac interface with a strong underlying UNIX? operating system for increased performance and stability.

MAILING LIST: An e-mail based discussion group. Sending one e-mail message to the mailing list’s list server sends mail to all other members of the group. Users join a mailing list by subscribing. Subscribers to a mailing list receive messages from all other members. Users have to unsubscribe from a mailing list to stop receiving messages forwarded from the group’s members.

MALWARE: The adware designed to monitor your keyboard keystrokes so that the author of the software can gain access to your password protected accounts are referred to as “malware” due to its malicious intent. MEGABYTE (MB): About a million bytes of space. Actually it’s 2 raised to the 20th power or 1,048,576 bytes of space.

MEMORY: Temporary storage for information, including applications and documents. The information must be stored to a permanent device, such as a hard disc or CD-ROM before the power is turned off, or the information will be lost. Computer memory is measured in terms of the amount of information it can store, commonly in megabytes or gigabytes.

MENU: A context-related list of options that users can choose from.

MENU BAR: The horizontal strip across the top of an application’s window. Each word on the strip has a context sensitive drop-down menu containing features and actions that are available for the application in use.

MERGE: To combine two or more files into a single file.

MHz: An abbreviation for Megahertz, or one million hertz. One MHz represents one million clock cycles per second and is the measure of a computer microprocessor’s speed. For example, a microprocessor that runs at 300 MHz executes 300 million cycles per second. Each instruction a computer receives takes a fixed number of clock cycles to carry out, therefore the more cycles a computer can execute per second, the faster its programs run. Megahertz is also a unit of measure for bandwidth.

MICROPROCESSOR: A complete central processing unit (CPU) contained on a single silicon chip.

MINIMIZE: A term used in a GUI operating system that uses windows. It refers to reducing a window to an icon, or a label at the bottom of the screen, allowing another window to be viewed.

MICROCOMPUTER: A microprocessor-based computer, consisting of an MPU, internal semiconductor memory, input and output sections, and a system bus, all on one, or several monolithic IC chips inserted into one or several PC boards. The addition of a power supply and connecting cables, appropriate peripherals (keyboard, monitor, printer, disk drives, etc.), an operating system and other software programs can provide a complete microcomputer system. The microcomputer is generally the smallest of the computer family, however, the improvement in performance capability of newer microcomputer systems can make the microcomputer as powerful as larger systems.

MICROPROCESSOR UNIT (MPU): The Central Processor Unit (CPU) implemented in monolithic IC technology, usually, but not necessarily, on one VLSI chip. In many cases, the SYSTEM BUS is also included on the MPU chip.

MIDI: Stands for Music Instrument Digital Interface. It allows a computer to store and replay a musical instrument’s output.

MINICOMPUTER: Considered to be more capable than a microcomputer but less powerful than a mainframe. Generally, the WORD-WIDTH of the minicomputer is between 12 to 32 bits.

MIME (Multipurpose Internet Mail Extensions): A set of Internet functions that extends normal e-mail capabilities and enables computer files to be attached to e-mail. Files sent by MIME arrive at their destination as exact copies of the original so that you can send fully-formatted word processing files, spreadsheets, graphics images and software applications to other users via simple e-mail. Aladdin’s Stuffit Expander will automatically convert MIME files.

MNEMONIC: A symbolic label or code reminder that assists the user in remembering a specific operation or command.

      See ASSEMBLY LANGUAGE.

MODEL: A representation of a process or system that can be controlled to demonstrate the effects that various actions will have on the process or system.

MONITOR: The visual readout device of a computer system. A monitor can be in several forms:, a cathode ray tube (CRT), a liquid crystal display (LCD), or a flat-panel, full-color display. See DISPLAY.

MODEM: A device that connects two computers together over a telephone or cable line by converting the computer’s data into an audio signal. Modem is a contraction for the process it performs: modulate-demodulate.

MOSAIC: The first Web browser to have a consistent interface for the Macintosh, Windows, and Unix environments. It was created at the National Center for Supercomputing Applications (NCSA). The success of this browser is really responsible for the expansion of the Web.

MOUSE: A small hand-held device, similar to a trackball, used to control the position of the cursor on the video display; movements of the mouse on a desktop correspond to movements of the cursor on the screen.

MP3:Stands for MPEG (Moving Picture Expert Group) Audio Layer 3. This is a compression standard that was developed to create a small audio file size while keeping a high quality sound. The small file size allows the sound to be streamed or downloaded over the Internet with ease.

MP4: Stands for MPEG (Moving Picture Expert Group): 4. Finalized toward the end of 1998, this became an International Standard in the beginning of 1999. This was developed to provide low bandwidth multimedia applications.

MPEG: Stands for Motion Picture Experts Group. A format to make, view, and transfer both digital audio and digital video files.

MULTITASKING: The technique of using several applications programs (tasks) in a computer system or on several terminals in a network at the same time. Multitasking can simultaneously work with several programs or interrelated tasks that share memories, codes, buffers, and files.

MULTIUSER: The term describing the capability of a computer system to be operated at more than one terminal at the same time.

MULTIPLEXER This is a piece of hardware that allows one item to take the place of several. An example would be using a multiplexer to allow 10 computers to attach where only one could before. 
MULTIMEDIA: Software programs that combine text and graphics with sound, video, and animation. A multimedia PC contains the hardware to support these capabilities.