GIS Dictionary

[astronomy] An orbit 22,245 miles (35,800 kilometers) above the equator in which a satellite travels at the same speed that the earth rotates. The Clarke Belt was named after the … Read more

[geodesy] A reference ellipsoid having a semimajor axis of approximately 6,378,206.4 meters and a flattening of 1/294.9786982. It is the basis for the North American Datum of 1927 (NAD27) and … Read more

1 [data analysis] A set of entities grouped together on the basis of shared attribute values. 2 [data models] Pixels in a raster file that represent the same condition. 3 … Read more

A set of categories for classification that divide the range of all values so that each piece of data is contained within a nonoverlapping category.

[cartography] The process of sorting or arranging entities into groups or categories; on a map, the process of representing members of a group by the same symbol, usually defined in … Read more

[ESRI software] An ASCII file in the geocoding rule base that identifies and classifies keywords that may appear in an address, such as street types and directions. Classification tables have … Read more

[programming] Acronym for Connected Limited Device Configuration. A framework for developing J2ME applications for devices with very limited resources, such as wireless devices.

[data quality] Data that is free from error.

[data conversion] Improving the appearance of scanned or digitized data by correcting overshoots and undershoots, closing polygons, performing coordinate editing, and so on.

[data sharing] A repository structure, physical or virtual, that collects, stores, and disseminates information, metadata, and data. A clearinghouse provides widespread access to information and is generally thought of as … Read more

[computing] An application, computer, or device in a client/server model that makes requests to a server.

[ESRI software] An address locator that is created and used on the same computer.

[computing] A software system with a central processor (server) that accepts requests from one or more user applications, computers, or devices (clients). Although client/server architecture can exist on one computer, … Read more

A map that represents slope with colors or shading.

[ESRI software] A command that extracts features from one feature class that reside entirely within a boundary defined by features in another feature class.

[computing] In object-oriented programming, the process of creating a new instance of a class with the same state as an existing instance.

[surveying] In surveying, a traverse that starts and ends with the same survey point.

[ESRI software] In ArcGIS Network Analyst, a type of network analysis for finding the closest locations (facilities) from sites (incidents), based on the impedance chosenfor example, finding hospitals near a … Read more

[surveying] 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 … Read more

[ESRI software] The summary of the difference between the endpoint coordinate of a traverse and the calculated endpoint.

[non-ESRI software] Acronym for common language runtime. The execution engine for .NET Framework applications, providing services such as code loading and execution and memory management.

[computing] Acronym for class identifier. A COM term referring to the globally unique number that is used by the system registry and the COM framework to identify a particular coclass.

[statistics] A statistical classification technique for dividing a population into relatively homogeneous groups. The similarities between members belonging to a class, or cluster, are high; while similarities between members belonging … Read more

[ESRI software] The minimum tolerated distance between vertices in a topology. Vertices that fall within the set cluster tolerance are snapped together during the topology validation process.

[ESRI software] A part of the topology validation process in which vertices that fall within a specified distance (cluster tolerance) of each other are snapped together.