C
CAD
See computer-aided design.
CAD dataset
A feature dataset representation of a CAD drawing. A CAD feature dataset is composed of feature classes representing all the points, lines, polygons, or annotation in the CAD drawing. For example, a CAD drawing may contain two line layers representing roads and parcel boundaries, respectively. The CAD dataset's line feature class represents all features in both the road and parcel boundary layers. A CAD dataset can contain wld files to put CAD drawings and data in geographic units rather than page units.
CAD drawing
The digital equivalent of a drawing, figure, or schematic created using a CAD system—for example, a drawing file or DWG file in AutoCAD.
An item in the Catalog tree representing all features and annotation in a CAD file. When you add a CAD drawing to a map or preview its contents in ArcCatalog, features are drawn using the symbology defined in the CAD file.
CAD feature class
A feature class in a CAD dataset. A CAD feature dataset is comprised of feature classes representing all the points, lines, polygons, or annotation in the CAD drawing. For example, a CAD drawing may contain two line layers representing roads and parcel boundaries, respectively. The CAD dataset's line feature class represents all features in both the road and parcel boundary layers.
candidates
A record from a geocoding reference data source that is a potential match for an address.
caption
The text for a command that appears with the "Text Only" and "Image and Text" display types-for example, the name of a menu or menu commands.
cardinality
A property of a relationship. Cardinality describes how many objects of type A are associated with how many objects of type B. Relationships can have many-to-one, one-to-one, one-to-many, and many-to-many cardinalities.
CASE
Computer-Aided Software Engineering. Consists of tools and techniques that automate the process of developing software systems or schemas. Complex tasks that often require many lines of code are simplified with CASE user interfaces and code generators.
Catalog tree
Contains a set of folder connections in ArcCatalog that provide access to geographic data stored in folders on local disks or shared on the network. It also includes folders that let you manage database connections and coordinate systems. The Catalog tree provides a hierarchical view of the geographic data in those folders.
categorical raster
A raster that represents the world with a set of values that have been aggregated into classes. For example, a satellite image that has been reclassified to extract a number of landcover types is a categorical raster. Categorical rasters represent an area, but the values do not form a continuous surface. See raster.
cell
Also known as raster cell or grid cell. A discretely uniform unit (square or rectangle) that represents a portion of the earth such as a square meter or square mile. Each grid cell has a value that corresponds to the feature or characteristic at that site such as a soil type, census tract, or vegetation class.
cell size
The length in map units of the side of a cell of a raster. The cell size is the same in both the x and y directions.
cell statistics
A Spatial Analyst function that calculates a statistic for each cell of an output raster that is based on the values in the same cell location of each cell of multiple input rasters.
central meridian
The line of longitude that defines the center and often the x origin of a projected coordinate system.
chart
A graphic representation of tabular data. Also referred to as a graph.
circle
A geometric shape for which the distance from the center to any point on the edge is equal.
class
A group or category of attribute values.
The interface by which an application program accesses the operating system and other services.
classifying
The process of sorting or arranging attribute values into groups or categories; all members of a group are represented on the map by the same symbol.
client/server
A software system is said to have a client/server architecture when there is a central process (server) that accepts requests from multiple user processes called clients.
cluster tolerance
The distance range in which all vertices and boundaries in a shapefile or feature dataset are considered identical, or coincident. A user-specified tolerance for the Integrate command in ArcMap. For example, if the cluster tolerance is set to 10 map units, after running Integrate there will be no more than one vertex within 10 map units of another.
coded value domain
Specifies a valid set of values for an attribute. Can apply to any kind of attribute—text, numeric, date, and so on. See also attribute domain.
coincident
Vertices or boundaries are coincident when they are within the cluster tolerance of one another. See also cluster tolerance.
color ramp
A range of colors used in a map to show ranking or order of feature attributes.
column
The vertical dimension of a table. A column has a name and a data type applied to all values in the column. See also item, field, and attribute.
COM
Component Object Model. The Component Object Model is a technology, not a programming language. COM is a binary specification from Microsoft that establishes a common way of building software components. COM objects have interfaces that contain methods and properties.
COM object
An object that implements its methods and properties through interfaces. COM objects behave as servers that interact with clients through one or more interfaces. Client code grabs a COM object's interface and tells that object to perform a function or manipulate a property. COM components can be dynamically interchanged in a distributed system with Dynamic Link Libraries (DLLs are in-process servers) and executable programs (EXEs are out-of-process servers).
combo box
A user interface tool that combines the features of an edit box and a list box. A combo box lets you type information or choose an option from a list. For example, the Location combo box in ArcCatalog lets you select an item in the Catalog tree by typing its path or choosing a path from its dropdown list.
command
An instruction that, when issued by the user, causes an application to perform an action. A command can be typed on a keyboard, chosen from a menu or toolbar, or embedded in program code.
complex edge feature
In a geodatabase, a linear network feature that corresponds to one or more network elements in the logical network. See also simple edge feature.
complex junction feature
In a geodatabase, a junction feature that corresponds to more than one network element in the logical network. For example, the state of the junction determines whether features can be connected or disconnected. See also simple junction feature.
composite relationship
Composite relationships describe associations where the lifetime of one object controls the lifetime of its related objects. An example is the association between highways and points for placing a highway shield marker. Shield points can't exist without a highway. See also relationship and simple relationship.
compress
The process of removing all database states that are no longer referenced by a version, and moving all rows in the delta tables (which are common to all versions) to the base table in a multiversioned geodatabase.
computer-aided design (CAD)
An automated system for the design, drafting, and display of graphically oriented information. Also known as computer-aided drafting.
concurrency management
A database management process for maintaining the consistency of the data while supporting simultaneous access by more than one user. A typical technique is to use a system of locking data to prevent data corruption caused by multiple users concurrently editing and reading data.
conflict
When multiple users simultaneously edit a version or reconcile two versions, conflicts can occur. Conflicts occur when the same feature or topologically related features are edited in both the edit and reconciliation versions, and the database is unclear about which representation is valid. See also conflict resolution.
conflict resolution
The process of resolving conflicting edits in two versions of the same dataset. Resolving a conflict requires that you make a conscious decision about the feature's correct representation and identify it in the Conflict Resolution dialog box. See also conflict.
conformal projection
A projection on which all angles at each point are preserved. Also called an orthomorphic projection (Snyder and Voxland, 1989). See also tangent projection and secant projection.
conic projection
A projection resulting from the conceptual projection of the earth onto a tangent or secant cone, which is then cut lengthwise and laid flat (Snyder and Voxland, 1989). See also tangent projection and secant projection.
connection
A mechanism in ArcCatalog used to access remote file systems and shared databases. Users establish connections to access remote or shared information.
connectivity
In a geodatabase, the state of edges and junctions in a logical network that controls flow, tracing, and pathfinding.
The topological identification in a coverage of connected arcs by recording the from-node and to-node for each arc. Arcs that share a common node are connected. See also arc–node topology.
connectivity rules
In a geodatabase, network rules that constrain the type of network features that may be connected to one another, and the number of features of any particular type that can be connected to features of another type. In most networks, not all edge types can logically connect to all junction types. Similarly, not all edge types can logically connect to all other edge types through all junction types. There are two types of connectivity rules: edge–junction and edge–edge.
constraints
Limits imposed on a model to maintain data integrity. For example, in a water network model, an 8-inch pipe can't connect to a 4-inch pipe.
Content Standard for Digital Geospatial Metadata
A metadata style guide authored by the FGDC. All U.S. government agencies (federal, state, and local) that receive federal funds to create metadata must create metadata following this standard.
contiguity
In coverages, the topological identification of adjacent polygons by recording the left and right polygons of each arc. See also polygon-arc topology.
continuous raster
A raster that represents the world with a set of values that vary continuously to form a surface. For example, a raster digital elevation model and an interpolated chemical concentration surface are continuous rasters.
contour
A line that connects points of equal value on a terrain surface (an isoline).
control points
Points you establish on a paper map whose coordinates represent known ground points or specific locations. Control points are used to register a paper map before you begin digitizing features on it using a digitizer.
conversion
A Spatial Analyst function. The process of converting input data from one representation to another, such as raster to vector.
coordinate
A set of numbers that designate location in a given reference system, such as x,y in a planar coordinate system or x,y,z in a three-dimensional coordinate system. Coordinate pairs represent a location on the earth's surface relative to other locations. See also vector.
coordinate system
A reference system used to measure horizontal and vertical distances on a planimetric map. A coordinate system is usually defined by a map projection, a spheroid of reference, a datum, one or more standard parallels, a central meridian, and possible shifts in the x- and y-directions to locate x,y positions of point, line, and area features.
In ArcInfo, a system with units and characteristics defined by a map projection. A common coordinate system is used to spatially register geographic data for a given area.
A reference system consisting of a set of points, lines, and/or surfaces, and set of rules used to define the positions of points in space either in two or three dimensions.
cost grid
An input dataset necessary to run the cost weighted distance function using Spatial Analyst. It identifies the cost of traveling through each cell in the grid. The Cost Weighted Distance function uses this cost grid to calculate the accumulative cost of traveling from every cell in the grid to a source or a set of sources.
Cost Weighted Allocation
A Spatial Analyst function that identifies the nearest source from each cell in a cost weighted distance grid. Each cell is assigned to its "nearest" source cell, in terms of accumulated travel cost.
Cost Weighted Direction
A Spatial Analyst function that provides a road map from the Cost Weighted Distance grid, identifying the route to take from any cell, along the least-cost path, back to the nearest source.
Cost Weighted Distance
A Spatial Analyst function that uses a cost grid to assign a value—the least accumulative cost of getting back to the source—to each cell of an output grid.
coverage
A file-based vector data storage format for storing the location, shape, and attributes of geographic features. A coverage usually represents a single theme such as soils, streams, roads, or land use. It is one of the primary vector data storage formats for ArcInfo. A coverage stores geographic features as primary features (such as arcs, nodes, polygons, and label points) and secondary features (such as tics, map extent, links, and annotation). Associated feature attribute tables describe and store attributes of the geographic features.
coverage units
The units (for example, feet, meters, inches) of the coordinate system in which a coverage is stored.
current task
During editing in ArcMap, a setting in the Current Task dropdown list that determines the task with which the sketch construction tools (Sketch, Arc, Distance-Distance, and Intersection) will work. The current task is set by clicking a task in the Current Task dropdown list.
custom behavior
Behavior is the implementation of an object class method. ESRI-provided objects have a set of methods associated with them. A developer can choose to override one of these methods or create additional methods. In this instance, the object is said to have custom behavior.
custom feature
In geodatabases, a feature with specialized behavior instantiated in a class by a developer.
custom tool
In ArcToolbox, a tool created by a user and added to the My Tools toolset.
custom toolset
A folder created by a user to hold custom tools or a group of frequently used ArcToolbox tools. It is created and stored with the ArcToolbox My Tools toolset.
cylindrical projection
A projection resulting from the conceptual projection of the earth onto a tangent or secant cylinder, which is then cut lengthwise and laid flat (Snyder and Voxland, 1989). See also tangent projection and secant projection.

B
background
You can set the color of the background of a scene to suggest sky, empty space, or any color that suits your visualization purpose. The default background color is white.
Some rasters (typically images) have border areas that are outside of the area for which image data was collected. This area is often assigned an arbitrary value (often black, or 255). You can control the display of these parts of a raster by setting the background color on the Symbology tab of the Layer Properties dialog box. See also nodata.
backup
A copy of a file, a set of files, or an entire disk for safekeeping in case the original is lost or damaged.
band
A measure of a characteristic or quality of the features observed in a raster. Some rasters have a single band; others have more than one. For example, satellite imagery commonly has multiple bands representing different wavelengths of energy along the electromagnetic spectrum.
barrier
An object that is placed on a map to specify the point in a network past which a trace cannot continue.
A line that limits the search for input sample points when performing interpolation. The line can represent a cliff, ridge, or some other interruption in the landscape. Only the sample points on the same side of the barrier as the current processing cell will be considered.
base height
The height at which a surface, raster, or feature draws in a scene. You can set the base height for features and rasters from a surface or by using a constant value or expression. Features with z-values stored in their geometry can have their base height set using the z-values. Setting the base heights from a surface is also called draping.
batch mode operation
Operates a given ArcToolbox tool to process a set of information, or a batch, rather than applying the tool to one piece at a time.
batch table
Displays the input name, user-selected parameters, and output name, where applicable, for all batch entries in ArcToolbox.
behavior
Properties of an object in a geodatabase that describe how it can be edited and drawn. Behavior includes, but is not limited to, validation rules, subtypes, default values, and relationships.
bin
A classification of lags in which all lags that have similar distance and direction are put into the same bin. Bins are commonly formed by dividing the sample area into grid cells or sectors.
BLOB
Binary large object. The binary data type of a column in an RDBMS table that stores large image, text, or geometry data as attributes.
bookmark
See spatial bookmark.
Boolean expression
A type of expression that reduces to a true or false (logical) condition. A Boolean expression contains logical expressions (for example, DEPTH > 100) and Boolean operators.
Boolean operator
A keyword that specifies how to combine simple logical expressions to define a complex expression. Boolean operators include AND, NOT and OR. For example, DEPTH>100 AND DIAMETER>20.
Operators within the Raster Calculator of Spatial Analyst. They use Boolean logic (TRUE or FALSE) on the input grids on a cell-by-cell basis. Output values of TRUE are written as 1, and values of False are written as 0.
Boolean operators: and, or, xor, not. For example: ingrid1 or ingrid2.
breakline
A line that marks a change in the shape of a surface. See TIN.
buffer
A zone of a specified distance around features. Both constant- and variable-width buffers can be generated. Buffers are useful for proximity analysis (for example, find all stream segments within 300 feet of a proposed logging area).
button
A command that runs a macro or custom code when clicked. Buttons can be added to any menu or toolbar. When they appear in a menu, buttons are referred to as menu commands.