GIS Glossary/M

GIS Glossary

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macro
A computer program, usually a text file, containing a sequence of commands that are executed as a single command. Macros are used to perform commonly used sequences of commands or complex operations.

magnetic bearing
A bearing measured relative to magnetic north.

magnetic declination
The angle between magnetic north and true north observed from a point on the earth. Magnetic declination varies from place to place, and changes over time, in response to changes in the earth's magnetic field.

magnetic north
The direction from a point on the earth's surface following a great circle toward the magnetic north pole, indicated by the north-seeking end of a compass.

magnetometer
An instrument used to measure variations in the strength and direction of the earth's magnetic field.

Magnifier window
A secondary window in ArcMap data view that shows a magnified view of a small area without changing the map extent. Moving the Magnifier window around will not affect the current map display.

maintenance license
A license that has a current maintenance contract with ESRI Customer Service. ESRI software users who have maintenance licenses are eligible for upgrade to the latest version of the software.

maintenance renewal
The date a maintenance contract expires for a particular product. Multiple copies of the same product may expire on different dates.

major axis
The longer axis of an ellipse or spheroid.

majority resampling
A technique for resampling raster data in which the value of each cell in an output is calculated, most commonly using a 2x2 neighborhood of the input raster. Majority resampling does not create any new cell values, so it is useful for resampling categorical or integer data, such as land use, soil, or forest type. Majority resampling acts as a type of low-pass filter for discrete data, generalizing the data and filtering out anomalous data values.

make permanent
In ArcGIS Spatial Analyst, an option that creates a permanent raster (one that is saved to disk) from a temporary result.

managed raster catalog
A raster catalog in which the raster datasets are copied to a location assigned by a geodatabase. When a row is deleted from a managed raster catalog, the data is deleted as well.

many-to-many relationship
An association between two linked or joined tables in which one record in the first table may correspond to many records in the second table, and vice versa.

many-to-one relationship
An association between two linked or joined tables in which many records in the first table may correspond to a single record in the second table.

map
A graphic representation of the spatial relationships of entities within an area.

map algebra
A language that defines a syntax for combining map themes by applying mathematical operations and analytical functions to create new map themes. In a map algebra expression, the operators are a combination of mathematical, logical, or Boolean operators (+, &gt;, AND, tan, and so on), and spatial analysis functions (slope, shortest path, spline, and so on), and the operands are spatial data and numbers.

map annotation
In ArcGIS, text or graphics stored within the map data frame in an annotation group. Map annotation may be manually entered or generated from labels, and can be individually selected, positioned, and modified.

map cache
A setting used in ArcMap that allows temporary storage of geodatabase or ArcIMS feature service features from a given map extent in the desktop computer's RAM, which may result in performance improvements in ArcMap for editing, feature rendering, and labeling.

map collar
Any of the supporting objects or elements that help a reader interpret a map. Typical map surround elements include the title, legend, north arrow, scale bar, border, source information and other text, and inset maps.

map configuration file
In ArcIMS, the file that contains the core site information. ArcIMS configuration files contain all the basic information about the content to be delivered, such as location of the data and layer symbology. Typically, a configuration file contains data that defines map content and has a file extension of .axl, but it can also be used to deliver metadata or route data (as .axl files) and to serve maps created in ArcMap (.mxd or .pmf files). Regardless of their type, configuration files contain content that the service registers to the ArcIMS spatial server and Web server for processing.

map display
A graphic representation of a map on a computer screen.

map document
In ArcMap, the file that contains one map, its layout, and its associated layers, tables, charts, and reports. Map documents can be printed or embedded in other documents. Map document files have a .mxd extension.

map element
In digital cartography, a distinctly identifiable graphic or object in the map or page layout. For example, a map element can be a title, scale bar, legend, or other map-surround element. The map area itself can be considered a map element; or an object within the map can be referred to as a map element, such as a roads layer or a school symbol.

map extent
The limit of the geographic area shown on a map, usually defined by a rectangle. In a dynamic map display, the map extent can be changed by zooming and panning.

map feature
A representation of a real-world object on a map.

map generalization
Decreasing the level of detail on a map so that it remains uncluttered when its scale is reduced.

Map Image Web Service
A SOAP ArcWeb service that provides dynamic map content for Internet applications. With this service, users input a geographic extent and several optional items (such as themes, type of map, size of image, map annotation) and receive the location of an output image file. Map Image Web Service provides access to services from a variety of leading data publishers.

map library
In ArcInfo Workstation Map Librarian, a collection of geographic data partitioned spatially as a set of tiles and thematically as a set of layers, indexed by location for rapid access.

Map Production System
The cartographic component of the Production Line Tool Set (PLTS). MPS is designed to facilitate large-volume cartographic production by providing the ability to create dynamic map layouts, batch symbology, and enhanced cartographic editing tools.

map projection
A method by which the curved surface of the earth is portrayed on a flat surface. This generally requires a systematic mathematical transformation of the earth's graticule of lines of longitude and latitude onto a plane. Some projections can be visualized as a transparent globe with a light bulb at its center (though not all projections emanate from the globe's center) casting lines of latitude and longitude onto a sheet of paper. Generally, the paper is either flat and placed tangent to the globe (a planar or azimuthal projection) or formed into a cone or cylinder and placed over the globe (cylindrical and conical projections). Every map projection distorts distance, area, shape, direction, or some combination thereof.

map query
A statement or logical expression that selects geographic features based on location or spatial relationship. For example, a spatial query might find which points are contained within a polygon or set of polygons, find features within a specified distance of a feature, or find features that are adjacent to each other.

map reading
The activity of viewing a map in a way that allows the viewer to make sense of or gain information from it. Map reading involves interpreting the meanings of codes and cartographic representations used on the map.

map scale
The ratio or relationship between a distance or area on a map and the corresponding distance or area on the ground, commonly expressed as a fraction or ratio. A map scale of 1/100,000 or 1:100,000 means that one unit of measure on the map equals 100,000 of the same unit on the earth.

map series
A collection of maps usually addressing a particular theme.

map service
A type of Web service that generates maps.

map sheet
A single map or chart in a map series, such as any one of the approximately 57,000 USGS 7.5-minute topographic maps of the United States and its territories.

map style
An organized collection of predefined colors, symbols, properties of symbols, and map elements. Styles promote standardization and consistency in mapping products.

map surround
Any of the supporting objects or elements that help a reader interpret a map. Typical map surround elements include the title, legend, north arrow, scale bar, border, source information and other text, and inset maps.

map template
In ArcMap, a kind of map document that provides a quick way to create a new map. Templates can contain data, a custom interface, and a predefined layout that arranges map elements, such as north arrows, scale bars, and logos, on the virtual page. Map templates have a .mxt file extension.

map topology
A temporary set of topological relationships between coincident parts of simple features on a map, used to edit shared parts of multiple features.

map unit
The ground unit of measurement&#8212;for example, feet, miles, meters, or kilometers&#8212;in which coordinates of spatial data are stored.

MapServer
An ArcGIS Server software component that provides programmatic access to the contents of a map document on disk and creates images of the map contents based on user requests. It is designed for use in building map-based Web services and Web applications using ArcGIS Server.

MapTip
In ArcGIS, a user-assistance component that displays an on-screen description of a map feature when the mouse is paused over that feature.

marginalia
Any of the supporting objects or elements that help a reader interpret a map. Typical map surround elements include the title, legend, north arrow, scale bar, border, source information and other text, and inset maps.

marker symbol
A symbol used to represent a point location on a map.

market area
A geographic zone containing the people who are likely to purchase a firm's goods or services.

market penetration analysis
A process that determines the percentage of a market area being reached based on the number of customers within an area divided by the total population in that area.

marshalling
The process that enables communication between a client object and server object in different apartments of the same process, between different processes, or between different processes on different machines by specifying how function calls and parameters are to be passed over these boundaries.

mashup
In Internet mapping, the combination of content from more than one data source into one dynamic map service.

mask
In digital cartography, a means of covering or hiding features on a map to enhance cartographic representation. For example, masking is often used to cover features behind text to make the text more readable.

mass point
An irregularly distributed sample point, with an x-, y-, and z-value, used to build a triangulated irregular network (TIN). Ideally, mass points are chosen to capture the more important variations in the shape of the surface being modeled.

master checkout version
In ArcGIS 9.1 and previous versions, the data version in the master geodatabase, created when data is checked out, that represents the state of the data at the time it was checked out.

master geodatabase
In ArcGIS 9.1 and previous versions, a geodatabase from which data has been checked out.

master site
In Business Analyst, the site of a known, well-performing business.

match score
In geocoding, a value assigned to all potential candidates for an address match. The match score is based on how well the location found in the reference data matches with the address data being searched.

matching
In geocoding, the process of linking a record, such as an address, to a set of reference data. The matched record in the reference data is used to determine the location of the input address.

mathematical expression
A kind of expression that evaluates to a number which is then typically stored in a variable, a field on a table row, or a cell in a raster dataset. Mathematical expressions are generally part of an algebraic equation:Result = Expression[PropertyTax] = ( [LandValue] * 0.75 ) + ( [StructureValue] * 0.50 )

mathematical function
In ArcGIS Spatial Analyst, a function that applies a mathematical operation to the values of a single input raster. There are four groups of mathematical functions available: logarithmic, arithmetic, trigonometric, and powers.

mathematical model
In Survey Analyst for field measurements, a set of relations between measurements and unknown coordinates.

mathematical operator
The symbolic representation of a process or operation performed against one or more operands in an expression, such as "+" (plus, or addition) and "&gt;" (greater than). When evaluated, operators return a value as their result. If multiple operators appear in an expression, they are evaluated in order of their operator precedence.

matrix
A rectangular arrangement of data, usually numbers, in rows and columns. In computer science, a two-dimensional array is called a matrix. In GIS, matrices are used to store raster data.

MAUP
Acronym for modifiable areal unit problem. A challenge that occurs during the spatial analysis of aggregated data in which the results differ when the same analysis is applied to the same data, but different aggregation schemes are used. MAUP takes two forms: the scale effect and the zone effect. The scale effect exhibits different results when the same analysis is applied to the same data, but changes the scale of the aggregation units. For example, analysis using data aggregated by county will differ from analysis using data aggregated by census tract. Often this difference in results is valid: each analysis asks a different question because each evaluates the data from a different perspective (different scale). The zone effect is observed when the scale of analysis is fixed, but the shape of the aggregation units is changed. For example, analysis using data aggregated into one-mile grid cells will differ from analysis using one-mile hexagon cells. The zone

max extent
The maximum bounding rectangle (in x,y coordinates) of an on-screen map. Users cannot zoom out beyond the max extent.

m-coordinate
In linear referencing, a measure value that is added to a line feature. M-values are used to measure the distance along a line feature from a vertex (a known location) to an event.

mean
The average for a set of values, computed as the sum of all values divided by the number of values in the set.

mean center
The location of a single x,y coordinate value that represents the average x-coordinate value and the average y-coordinate value of all features in a study area.

mean sea level
The average height of the surface of the sea for all stages of the tide over a nineteen-year period, usually determined by averaging hourly height readings from a fixed level of reference.

mean stationarity
In geostatistics, a property of a spatial process in which a spatial random variable has the same mean value at all locations.

measure
In linear referencing, a value stored along a linear feature that represents a location relative to the beginning of the feature, or some point along it, rather than as an x,y coordinate. Measures are used to map events such as distance, time, or addresses along line features.

measure location fields
In linear referencing, either one or two fields in a table that describe the position of an event along a route.

measure value
In linear referencing, a measure value that is added to a line feature. M-values are used to measure the distance along a line feature from a vertex (a known location) to an event.

measured grid
In cartography, any network of parallel and perpendicular lines superimposed on a map and used for reference. These grids are usually referred to by the map projection or coordinate system they represent, such as universal transverse Mercator grid.

measurement
An observed numerical value that is an appraisal of size, extent, or amount according to a set criteria.

measurement error
In surveying, the noise that is expected in every measurement. It occurs because the observer makes estimates and uses measuring equipment that is unpredictable in an environment that is also unpredictable.

measurement residual
The difference between a measured quantity and its theoretical true value as determined during each iteration of a least-squares adjustment.

median
The middle value of a set of values when they are ordered by rank. Half the values in a set are higher than the median, and half are lower. When there are two middle values (if the set has an even number of elements) the median is the mean of these two values.

median center
A location representing the shortest total distance to all other features in a study area.

medium-format printer
A printing device capable of producing an image on paper or other media sized between 15 and 35 inches (38 and 90 centimeters) wide. Medium-format printers typically use inkjet printing technology to print an image on a roll or sheet-fed media. While most large-format printers are large, free-standing units, most medium-format printers are small enough to fit on a desk.

members
Refers collectively to the properties and methods, or functions, of an interface or class.

memory cache
In ArcGlobe, the amount of system memory that the application will use.

memory leak
In computer programming, the loss of computer memory that occurs when an application or component fails to free a section of computer memory when it has finished using it. During a memory leak, the section of memory allocated by one application or component may not be used by any other application.

mental map
A person's perception of a place. A mental map may include the physical characteristics of a place, such as boundaries of a neighborhood, or the attributes of a place, such as a neighborhood's perceived unsafe areas. A mental map is primarily a psychological construct, although it may also be rendered as an actual map.

menu
A list of available commands or operations displayed on a computer screen from which a user can make a selection.

menu item
An item in a list of commands displayed on a menu.

mereing
Establishing a boundary relative to ground features present at the time of a survey.

merge policy
In geodatabases, rules that dictate what happens to the respective attributes of features that are merged together during editing in ArcMap. A merge policy can be set to assign a default value to the new attribute, summarize the values of the merged attributes, or create a weighted average from the merged attributes.

merging
Combining features from multiple data sources of the same data type into a single, new dataset.

meridian
A great circle on the earth that passes through the poles, often used synonymously with longitude. Meridians run north&#8211;south between the poles. By convention, meridians are labeled with positive numbers that ascend as one moves eastward from the prime meridian, and negative numbers as one moves westward from the prime meridian until the east and west hemispheres meet at the 180-degree line. Meridians can also, however, be labeled with all positive or negative numbers, including positive numbers increasing westward from the prime meridian.

metabase
In Microsoft Internet Information Services (IIS), an XML file where the IIS configuration information is stored.

metadata
Information that describes the content, quality, condition, origin, and other characteristics of data or other pieces of information. Metadata for spatial data may describe and document its subject matter; how, when, where, and by whom the data was collected; availability and distribution information; its projection, scale, resolution, and accuracy; and its reliability with regard to some standard. Metadata consists of properties and documentation. Properties are derived from the data source (for example, the coordinate system and projection of the data), while documentation is entered by a person (for example, keywords used to describe the data).

metadata element
A unit of information within metadata, used to describe a particular characteristic of the data.

Metadata Explorer
A Web application, developed using the ArcIMS Java Connector, that can be used to view metadata included in an ArcIMS metadata service.

metadata profile
A modification of an existing metadata standard to adapt to data issues, cultural issues, or both. A profile is typically a subset of a base standard that tailors the metadata elements in the base standard to better describe the data to the community that uses it. Metadata profiles allow communities to follow a metadata standard, while at the same time enhancing the standard so that it is more appropriate for a particular use or locale.

metadata server
A public ArcIMS virtual server that provides the capability to manage and search a central metadata repository. Data producers can publish their metadata to the repository while data consumers are able to search the repository to locate appropriate data.

metadata service
A service that uses the spatial server metadata capabilities, allowing users to publish and share metadata documents over the Internet or an intranet.

metes and bounds
A surveying method in which the limits of a parcel are identified as relative distances and bearings from landmarks. Metes and bounds surveying often resulted in irregularly shaped areas.

method
In object-oriented programming, an action that an object is capable of performing. Objects that belong to the same class all have the same methods. For example, all Visual Basic form objects can execute a method called "Show and Hide."

metropolitan statistical area
A geographic entity defined by the U.S. Office of Management and Budget for use by federal statistical agencies, including the U.S. Census Bureau. A metropolitan statistical area is based on the concept of a core area with a large population nucleus, plus adjacent communities having a high degree of economic and social integration with that core area. According to the 1990 standards, to qualify as a metropolitan statistical area, the area must include at least one city or urbanized area with 50,000 or more inhabitants and a total metropolitan population of at least 100,000 (75,000 in New England).

microdensitometer
A densitometer that can read densities in minute areas, used particularly for studying spectroscopic and astronomical images.

micrometer
An instrument for measuring minute lengths or angles.

micron
One millionth of a meter, represented by the symbol &#956;m. Microns are used to measure wavelengths in the electromagnetic spectrum.

micropolitan statistical area
A geographic region containing at least one urban area with a population between 10,000 and 50,000, defined by the U.S. Office of Management and Budget for use by federal statistical agencies, including the U.S. Census Bureau. Micropolitan statistical areas include adjacent communities having a high degree of economic and social integration with the core area.

MIDP
Acronym for Mobile Information Device Profile. A set of J2ME APIs for wireless devices.

Military Analyst extension
An ArcGIS extension that optimizes the effectiveness of core ArcGIS as a toolset foundation for military planners and intelligence analysts. Military Analyst is COM-compliant and extensible with ArcObjects.

MIL-STD-2525B Change 1
The military specification for common war fighting symbology; the U.S. military standard that provides guidelines and criteria for the development and display of standard C4I war fighting symbology.

mimetic symbol
A symbol that imitates or closely resembles the thing it represents, such as an icon of a picnic table that represents a picnic area.

min/max scale
The smallest and largest scales at which a layer is visible on a map. Scale ranges are used to prevent detailed layers from displaying when zoomed out and to prevent general layers from displaying when zoomed in.

minimum bounding rectangle
A rectangle, oriented to the x- and y-axes, that bounds a geographic feature or a geographic dataset. It is specified by two coordinate pairs: xmin, ymin and xmax, ymax.

minimum candidate score
In geocoding, the minimum score a potential match record requires to be considered a candidate. This value is adjustable on the Address Locator Properties dialog box.

minimum map unit
For a given scale, the size in map units below which a narrow feature can be reasonably represented by a line and an area by a point.

minimum match score
In geocoding, the minimum score a match candidate needs to be considered a match in batch geocoding. This value is adjustable on the Address Locator Properties dialog box.

minor axis
The shorter axis of an ellipse or spheroid.

minute
An angle equal to 1/60 of a degree of latitude or longitude and containing sixty seconds.

misclosure
A discrepancy between existing coordinates and computed coordinates that occurs when the final point of a closed traverse has known coordinates and the final course of a traverse computes different coordinates for the same survey point.

mixed list
In Survey Analyst for field measurements, one of two types of lists in the List page. The mixed list has a mixed set of rows that might have, for instance, survey points, coordinate geometry measurements, and a mix of different computations.

mixed pixel
In remote sensing, a pixel whose digital number represents the average of several spectral classes within the area that it covers on the ground, each emitted or reflected by a different type of material. Mixed pixels are common along the edges of features.

mobile toolkit
A J2ME-based toolkit for building mobile applications that use ArcWeb Services.

model
An abstraction of reality used to represent objects, processes, or events.

model generalization
The abstraction, reduction, and simplification of features and feature classes for deriving a simpler model of reality or decreasing stored data volumes.

model parameter
In ArcGIS, a type of parameter exposed in a geoprocessing model that displays in a model's dialog box and allows for input.

ModelBuilder
The interface used to build and edit geoprocessing models in ArcGIS.

modifiable areal unit problem
A challenge that occurs during the spatial analysis of aggregated data in which the results differ when the same analysis is applied to the same data, but different aggregation schemes are used. MAUP takes two forms: the scale effect and the zone effect. The scale effect exhibits different results when the same analysis is applied to the same data, but changes the scale of the aggregation units. For example, analysis using data aggregated by county will differ from analysis using data aggregated by census tract. Often this difference in results is valid: each analysis asks a different question because each evaluates the data from a different perspective (different scale). The zone effect is observed when the scale of analysis is fixed, but the shape of the aggregation units is changed. For example, analysis using data aggregated into one-mile grid cells will differ from analysis using one-mile hexagon cells. The zone

modifier
In MOLE, text or graphics that display around a symbol, or a value that changes the appearance of a symbol. In some military specifications, attributes are referred to as modifiers.

MODIS
Acronym for moderate resolution imaging spectroradiometer. A bundle of remote-sensing equipment housed on two NASA (National Aeronautics and Space Administration) satellites, Terra and Aqua, in orbit around Earth. These two MODIS-equipped satellites constantly record multiple images of the globe in various wavelengths and resolutions, imaging the earth's entire surface in less than two days.

MOLE
Acronym for Military Overlay Editor. An ESRI software application that allows users to create, display, and edit military symbology in their maps.

monochromatic
Related to a single wavelength or a very narrow band of wavelengths.

Monte Carlo method
An algorithm for computing solutions to problems that contain a large number of variables by performing iterations with different sets of random numbers until the best solution is found. The Monte Carlo method is usually applied to problems too complex for analysis by anything but a computer.

monument
An object, such as a metal disk, permanently mounted in the landscape to denote a survey station.

morphology
The structure of a surface.

mosaic
A raster dataset composed of two or more merged raster datasets&#8212;for example, one image created by merging several individual images or photographs of adjacent areas.

mouse mode
A way of using a digitizing tablet in which the digitizer puck behaves like a mouse; the puck is used to point to interface elements rather than to trace shapes on the surface of the digitizing tablet.

MPS
Acronym for Map Production System. The cartographic component of the Production Line Tool Set (PLTS). MPS is designed to facilitate large-volume cartographic production by providing the ability to create dynamic map layouts, batch symbology, and enhanced cartographic editing tools.

MSA
A geographic entity defined by the U.S. Office of Management and Budget for use by federal statistical agencies, including the U.S. Census Bureau. A metropolitan statistical area is based on the concept of a core area with a large population nucleus, plus adjacent communities having a high degree of economic and social integration with that core area. According to the 1990 standards, to qualify as a metropolitan statistical area, the area must include at least one city or urbanized area with 50,000 or more inhabitants and a total metropolitan population of at least 100,000 (75,000 in New England).

MSDN
Acronym for Microsoft Developer Network. A set of services designed to help developers write applications using Microsoft products and technologies.

MSS
A device carried on satellites and aircraft that records energy from multiple portions of the electromagnetic spectrum.

MTA
Acronym for multiple threaded apartment. An apartment that can have multiple threads running. A process can only have one MTA.

multichannel receiver
A receiver that tracks several satellites at a time, using one channel for each satellite.

multidimensional data
Data that is comprised of multiple dimensions, such as space and time. For example, a temperature dataset could have dimensions of latitude, longitude, altitude, and time.

multimodal network
A network in which two or more types of transportation modes (such as walking, riding a train, or driving a car) are modeled. In a network dataset, multiple connectivity groups are required to create a multimodal network.

multipart feature
In ArcGIS, a digital representation of a place or thing that has more than one part but is defined as one feature because it references one set of attributes. In a layer of states, for example, the state of Hawaii could be considered a multipart feature because its separate geometric parts are classified as a single state. A multipart feature can be a point, line, or polygon.

multipatch
In ArcGIS, a type of geometry comprised of planar three-dimensional rings and triangles, used in combination to model objects that occupy discrete area or volume in three-dimensional space. Multipatches may represent geometric objects like spheres and cubes, or real-world objects like buildings and trees.

multipatch feature
In ArcGIS, a real-world geographic feature modeled using multipatch geometry.

multipath error
Errors caused when a satellite signal reaches the receiver from two or more paths, one directly from the satellite and the others reflected from nearby buildings or other surfaces. Signals from satellites low on the horizon will produce more error.

multiple regression
Regression in which the dependent variable is measured against two or more independent variables.

Multiple Setup page
In the Survey Analyst for field measurements Survey Explorer, one of two types of setup pages. The Multiple Setup page is used for computations that process more than one instrument setup.

multiple threaded apartment
An apartment that can have multiple threads running. A process can only have one MTA.

multiplexing channel receiver
A receiver that tracks several satellite signals using a single channel.

multipoint
In ArcGIS software, a geometric element defined by an unordered set of x,y coordinate pairs.

multipoint feature
In ArcGIS software, a digital map feature that represents a place or thing that has neither area nor length at a given scale, and that is treated as a single object with multiple locations. For example, the entrances and exits to a prairie dog den might be represented as a multipoint feature. A multipoint feature is associated with a single record in an attribute table.

multipoint feature class
A feature class that can store many points per shape or row, thereby saving storage space and improving read-write performance.

multispectral
Related to two or more frequencies or wavelengths in the electromagnetic spectrum.

multispectral image
An image created from several narrow spectral bands.

multispectral scanner
A device carried on satellites and aircraft that records energy from multiple portions of the electromagnetic spectrum.

multiuser geodatabase
A geodatabase managed in an RDBMS server by ArcSDE. Multiuser geodatabases can be very large and support multiple concurrent editors. They are supported on a variety of commercial RDBMS, including IBM DB2, IBM Informix, Oracle, Microsoft SQL Server, and PostgreSQL.

multivariate analysis
Any statistical method for evaluating the relationship between two or more variables.

multiversioned view
In ArcGIS and ArcSDE, a view that uses stored procedures and triggers to access a specified version of data in a single business table in the geodatabase. A multiversioned view includes all the records in the business table that have been selected and merged with records from the delta tables. The schema of a multiversioned view is identical to that of the business table on which it is based.

m-value
In linear referencing, a measure value that is added to a line feature. M-values are used to measure the distance along a line feature from a vertex (a known location) to an event.

MXD
In ArcMap, the file that contains one map, its layout, and its associated layers, tables, charts, and reports. Map documents can be printed or embedded in other documents. Map document files have a .mxd extension.

My ArcWeb Locations
A feature in the ArcWeb Toolbar for ArcGIS that allows users to save and quickly access selected locations.

My Output Data folder
A computer file that contains all the work done in Business Analyst: study areas; analyses; and customer, store, and extracted data.

My services
The services that a user creates in Builder to use with ArcWeb Services.

My Toolboxes folder
In ArcCatalog, a folder that contains nonsystem toolboxes created in the ArcToolbox window or directly in the My Toolboxes folder in the ArcCatalog Tree. The My Toolboxes folder points to a location on disk that can be changed in the Geoprocessing tab of the Options dialog box, accessible from the Tools menu.