Barrons Publishing Dictionary of Computer and Internet Terms 10th

monospace a typeface design that gives each letter the same width, like this. See Figure 104, page 193. See also COURIER; FIXED-PITCH TYPE; TYPEFACE.

Monte Carlo engine a computer or program used for MONTE CARLO SIMULATION.

Monte Carlo simulation a simulation method that uses random numbers to estimate complex probabilities.

Suppose that you know the probability that a particular event will happen, but it is too difficult to calculate the probability that a complicated combination of events will occur. In the Monte Carlo method you use a random number generator to calculate a random number between 0 and 1, and then compare that number with the probability of the event. For example, if the probability of the event is .62, and the random number generated is .58, then the program will simulate that the event has occurred. You can simulate thousands of such events and look at how the combinations of them add up. The name Monte Carlo comes from the fact that this method is a bit like a game of chance.

MOO (MUD, Object Oriented) a type of MUD (Internet game or interaction environment). See MUD.

Moore’s Law the prediction that the number of transistors that can be placed in an INTEGRATED CIRCUIT of any given size will double every two years. That is why microprocessors and other integrated circuits become cheaper and more efficient year by year.

Moore’s Law was first expressed in 1967 by Gordon Moore, cofounder of Intel, and has proved accurate so far, although there is speculation that true physical limits will be reached within a few more years.

morph to transform one image gradually into another. A moving morph is an animation of the morphing process; a still morph is a single image of the transition in progress. See also ANIMATION; COMPOSITING.

FIGURE 172. Morph

Mosaic one of the first graphical BROWSERs for the World Wide Web, distributed free by the National Center for Supercomputer Applications (www.ncsa.uiuc.edu) and later incorporated into Microsoft Internet Explorer and other products.

motherboard the main circuit board of a computer, containing the CPU and memory

motion blur (paint, 3-d programs) a filter that blurs the image along a specified axis to give the effect of motion.

FIGURE 173. Motion blur

Motorola a major manufacturer of electronic equipment and parts, headquartered in Schaumburg, Illinois. Motorola makes a number of microprocessors, including the 68000 series used in the original Apple Macintosh, the PowerPC, and the 6800, used in some early microcomputers in the 1970s.

In 2004, Motorola spun off its microprocessor division as Freescale Semiconductor, Inc., headquartered in Austin, Texas. Web address: www.freescale.com.

mount to put a disk or tape into a computer and make it known to the operating system. Under UNIX, a list of all currently mounted file systems can be displayed by typing the command mount. Windows shows all mounted drives under COMPUTER; Macintosh computers display mounted drives on the DESKTOP.

mount point a directory that is actually a separate disk drive. For example, if a UNIX system has two disks, one of them will likely be mounted as / (the root directory) and the other as /home. Then the second disk drive will function as if it were a subdirectory of the first one.

mouse a computer input device that is used by moving it around on your desk and pressing one or more buttons. Moving the mouse moves a pointer on the screen (see MOUSE POINTER). Graphical user interfaces such as Microsoft Windows and the Apple Macintosh operating system are built around the mouse. So are paint and draw programs. See DRAW PROGRAM; GRAPHICAL USER INTERFACE; MACINTOSH; PAINT PROGRAM;

TRACKBALL; WINDOWS (MICROSOFT).

mouse pointer a small symbol on the screen (usually an arrow) that indicates what the mouse is pointing to, and moves whenever the mouse is moved. Also called mouse cursor.

mouse potato (slang) a computer user who is addicted to web-surfing and other computer-related activities. Obviously adapted from couch potato, a person who incessantly views television.

mouseover see ROLLOVER (definition 2).

mousetrap a web page that is programmed, using JavaScript or another scripting language, so that the “back” button on the browser no longer works as intended. That is, once you go to such a web page, you cannot back out of it. In 2001 the U.S. Federal Trade Commission took action against an advertiser who used mousetraps on thousands of web sites to compel viewers to view a barrage of obnoxious advertisements.

MOV

1. (metal oxide varistor) an electronic component used to protect electronic equipment from momentary voltage spikes. See

TECTION; SURGE PROTECTOR.

2.abbreviation for “move” in most ASSEMBLY LANGUAGES. The direction of the arguments depends on the language. On Intel processors, MOV 7,8 means move the value 8 into location 7; on Motorola processors it means move the value 7 into location 8.

3.file format used by QUICKTIME for movies and other media types.

Mozilla an open-source web browser established by Netscape; also the name of a lizard used as Mozilla’s mascot. Their web site is www.mozilla.org. See also FIREFOX.

MP3 a file compression format for music that allows users to download music over the web. MP3 is short for MPEG, layer 3 (layer 1 and layer 2 refer to previous, less-advanced compression formats) and is promoted by the Motion Picture Experts Group (see MPEG).

Sound waves can be represented as numbers indicating the amplitude of the wave at each moment in time. High-fidelity sound requires storing a 16-bit number 44,100 times per second (a sampling rate of 44.1 kilohertz). This means that one minute of stereo music requires over 10 megabytes of disk space. This is generally too large to be practical, but MP3 compression reduces the file size to about 1 megabyte per minute. The compression method was developed after carefully studying human auditory perception and then designing the compression algorithm so that the information lost is imperceptible.

MP3 format now allows many artists to make samples of their work available to the general public over the web, but the ease of copying music in MP3 format raises concerns about piracy. See also COPYRIGHT;

DRM; SOUND CARD; WAVE FILE. Compare OGG VORBIS.

MP3 player

1.a small portable device that stores and plays music in the form of MP3 files. Compare IPOD.

2.a computer program that plays music from MP3 files.

MPC (multimedia personal computer) a personal computer that meets requirements specified by the MPC Marketing Council for compact disc, sound, and graphics capabilities. These requirements are revised frequently.

MPEG (Motion Picture Experts Group) an ISO working group that sets standards for digital sound and video and the associated data compression requirements. Web address: www.mpeg.org.

MRU most recently used.

MRU list a list of most-recently-used files or web addresses. Many word processors, web browsers, and so on, maintain MRU lists so the user can quickly return to a document that was used recently. Windows maintains an MRU list on the Start button.

ms (millisecond) one thousandth of a second. See ACCESS TIME.

MS a common abbreviation for Microsoft. See MICROSOFT; MS-DOS.

MS-DOS Microsoft Disk Operating System, the original operating system for IBM PC-compatible computers. Early versions were also marketed by IBM as PC-DOS; later MS-DOS and PC-DOS became separate products derived from the same original code.

Virtually all the commands of DOS are still usable at the COMMAND PROMPT in Windows. See also BAT FILE; COM; EXE FILE; EXTENSION;

MICROSOFT; OS/2; PATH; WINDOWS.

MS-DOS Prompt the COMMAND PROMPT in Windows Me and earlier.

MSIE Microsoft INTERNET EXPLORER.

MSN (Microsoft Network) an online network established by Microsoft which provides content as well as a connection to the Internet.

MSRP manufacturer’s suggested retail price.

MTBF (mean time between failures) a measure of the reliability of equipment. For example, equipment with an MTBF of 25,000 hours can be expected to run, on the average, 25,000 hours without failing. Some disk drives have an MTBF as high as 800,000 hours (90 years). However, the MTBF is only an average; there is always a risk that any particular piece of equipment will fail sooner.

MUD (multi-user domain or multi-user dimension, formerly multi-user dungeon) a type of real-time Internet conference in which users not only talk to each other, but also move around and manipulate objects in an imaginary world.

Originally conceived as multi-user ADVENTURE GAMEs, MUDs have developed into a promising format for collaboration and education through the Internet. Compare IRC.

multicast see IPTV.

multimedia the combination of sound and visual information presented either to inform or to entertain.

Multimedia PC see MPC.

MultiMediaCard a type of flash-memory non-volatile storage device similar to CompactFlash but physically smaller, the size of a postage stamp, and often used in digital music players. Compare COMPACTFLASH; MEMORY STICK; SECURE DIGITAL CARD; SMARTMEDIA.

multiple inheritance a technique in object-oriented programming whereby an object type is defined to be a combination of two or more pre-exist- ing types. Some programming languages, such as C++, permit this, and others, such as Java, do not. See OBJECT-ORIENTED PROGRAMMING.

multiprocessing the use of more than one CPU in a single computer system.

multiprocessor free see FREE.

multisession CD a compact disc (CD-ROM) that was not recorded all at once; rather, some files were recorded on it at one time and more files were added later. The directory of a multisession CD occupies more than one block of disc space, and some of the earliest CD-ROM software could not read multisession CDs. See CD-ROM and references there.

multitasking the execution of more than one program apparently at the same time on the same computer. In reality, the CPU rapidly switches its attention among the various programs (see TIMESHARING). Multitasking makes it possible to print one document while editing another or to perform lengthy computations “in the background” while working on something else on the screen.

The programs that run concurrently are called processes or tasks. An important concern is to keep tasks from interfering with each other. For example, two tasks cannot use the same area of memory or the same input-output device, such as a printer, at the same time.

If tasks communicate with each other, it is important to prevent deadlocks, in which two tasks are each waiting for the other to do something, so that neither one can make any progress. See STARVATION.

Multitasking can be either preemptive or cooperative. In preemptive multitasking (as in Windows 95 and later versions, and UNIX) the operating system forces the CPU to switch regularly from each process to the next. In cooperative multitasking (as in Windows 3.0 and 3.1), each process has to voluntarily give up the CPU periodically so that other processes can run.

A more primitive form of multitasking allows you to switch from one program to another, but only one program at a time actually runs; the others are frozen until you return to them. This kind of multitasking was implemented in versions of Microsoft Windows before 3.0 and in early versions of the Macintosh operating system.

.museum a suffix indicating that a web or e-mail address belongs to a museum (in any country). Contrast .COM. See also ICANN; TLD.

MVS (Multiple Virtual Storage) an operating system for IBM mainframe computers; from the user’s point of view, it is almost completely compatible with OS/360. See JCL; OS/360; TSO: Z/OS.

mwahahahaha typewritten representation of an evil laugh.

My Computer a FOLDER on the DESKTOP of Microsoft Windows that contains all the disk drives, the Control Panel, and other information about the system.

Ordinarily, folders are directories. The root directory of a disk drive is also a folder. My Computer is a special folder that gives you access to the entire machine.

In Windows Vista, My Computer is called simply Computer.

My Documents a FOLDER on the DESKTOP of Microsoft Windows in which the user is invited to store his or her files in the absence of a more elaborate file system. The My Documents folder was created to discourage beginners from storing files in the same folder as the software that created them. In Windows Vista, My Documents is called simply Documents.

My Network Places the FOLDER on the Windows DESKTOP that enables the user to BROWSE (examine) the computer resources available through the network, if any. In Windows Vista, My Network Places is called simply Network.

MySpace the most popular SOCIAL NETWORKING SITE (www.myspace.com). MySpace lets users customize their profile pages to a high degree. Because of its popularity, MySpace is often at the center of concerns that affect all web sites, particularly regarding the safety and privacy of its younger users.

MySQL popular open-source database software. See SQL; www.mysql.com/.

nano- metric prefix meaning ÷1,000,000,000. For example, 1 nanosecond is one billionth of a second. Nano- is derived from the Latin word for “dwarf.” See METRIC PREFIXES.

nanometer (abbreviated nm) a distance of 10–9 meter, or a millionth of a millimeter. The wavelength of visible light is measured in nanometers, from violet (350 nm) to red (700 nm). The size of the parts of an INTEGRATED CIRCUIT is measured in nanometers. For example, a “45-nanome- ter process” is a manufacturing process that can reproduce details as small as 45 nanometers across.

nanosecond a unit of time equal to 10–9 second, that is to say, 1/1,000,000,000 second. During one nanosecond, a light wave, electrical field, or radio wave travels about one foot (30.5 cm). The access time of many computer memories is about 60 to 70 nanoseconds.

NAP (network access point) a location where an Internet service provider or other network connects to a BACKBONE to access the Internet. See also MAE.

Napster a company founded in 1999 to provide person-to-person sharing of MP3 music files. Instead of storing files in a central repository, Napster allowed any user to share music files anonymously with anyone else who wanted them. The resulting network traffic created temporary but serious overloads at some colleges and universities.

Napster’s file sharing system was shut down by court order in 2001 (A&M Records v. Napster). Napster now provides a service where users can obtain unlimited legal access to over one million songs in return for a monthly subscription fee. Web address: www.napster.com. See also

DIGITAL MUSIC; GROKSTER; ITUNES; MP3; P2P.

NAS see NETWORK ATTACHED STORAGE.

NAT see NETWORK ADDRESS TRANSLATION.

national characters the characters on a computer are those whose appearance varies from country to country. For example, on IBM mainframes, the characters $, #, and @ are called national characters because they may be replaced by other characters such as £ or ¥ for use outside the United States.

native

1.designed for a specific hardware or software environment (rather than for compatibility with something else).

2.consisting of CPU machine instructions rather than instruction codes to be interpreted by a program.

native file format the file format proprietary to an application program; the format in which it normally saves documents or drawings. Most programs can, with the IMPORT command, convert similar file types to their own format. If you want to convert a native file to a more generic file type, use the SAVE AS. . . or EXPORT commands. Contrast METAFILE.

native method a computer program compiled in the machine language of the specific computer on which it is being run. For example, a Java program is normally compiled to Java bytecode, but in some cases it might link to a native method that was written in a language such as C++ and compiled into machine language.

native resolution the RESOLUTION of a monitor determined by the available pixels. The sharpest image will occur if the number of pixels generated by the video processor matches the monitor’s available pixels. Other resolutions may be available, but the image may be less sharp as interpolation is required to determine the color for intermediate pixels.

natural language processing the use of computers to process information expressed in human (natural) languages.

Getting computers to understand English, French, or other human languages is a difficult, largely unsolved problem. It includes SPEECH RECOGNITION, syntactic PARSING to determine sentence structure, semantic analysis to determine meaning, and knowledge representation to encode the meaning into a computer. The challenge of natural language understanding is that human language is far more complicated, and more poorly understood, than early computer scientists realized.

It is much easier to process natural-language texts in a way that falls short of full understanding, but still allows some of the meaning to be extracted. In recent years, natural language technology has turned toward

INFORMATION EXTRACTION and INFORMATION RETRIEVAL to help manage the huge quantity of natural-language documents now stored in computers.

See also ARTIFICIAL INTELLIGENCE; ELIZA.

natural logarithm logarithm to the base e (about 2.718). See LOGARITHM.

FIGURE 175. Natural media paint program

natural media actual artists’ materials (paint, canvas, etc.) realistically simulated by a computer program (Figure 175). In a natural-media paint program, you can specify the kind of paper or canvas you are working on. The tools available behave very much as their real-world counter-