OGC Newsroom

Glossary of Terms - D

Definitions: 
Data Catalog Model
Source: The OpenGIS® Abstract Specification Topic 6: The Coverage Type and its Subtypes Version 6. http://www.opengis.org/techno/abstract/00-106.pdf
The general model for representing online data catalogs that pertain to enterprise data stores.
data clearinghouse
Source: ISO 19115
Collection of institutions providing digital data, which can be searched through a single interface using a common metadata standard.
data coordination
Organizations that seek to share GI working to reach consensus on common data models.
data domain
Source: GETIS glossary
Set of feature collections that is commonly used in a specific discipline or application. An example of a data domain is {roads, houses, rivers} or on another abstraction level {transport, buildings}
data infrastructure
Source: GETIS glossary
See SDI
data level
Source: ISO 19101
Stratum within a set of layered levels in which data is recorded that conforms to definitions of types found at the application model level
data model
Source: AGI glossary. http://www.geo.ed.ac.uk/agidict/welcome.html
"An abstraction of the real world which incorporates only those properties thought to be relevant to the application at hand. The data model would normally define specific groups of entities, and their attributes and the relationships between these entities. A data model is independent of a computer system and its associated data structures. A map is one example of an analogue data model."
data quality
Source: AGI glossary. http://www.geo.ed.ac.uk/agidict/welcome.html
"Indications of the degree to which data satisfies stated or implied needs. This includes information about lineage, completeness, currency, logical consistency and accuracy of the data"
data schema
Source: PreANVIL Glossary http://www.anvil.eu.com/find/Glossary-english.htm
Formal description of a data model
data semantics
Source: PreANVIL Glossary http://www.anvil.eu.com/find/Glossary-english.htm
The meaning of data: in the GI sector this includes the identification of related object classes embedded in different abstractions
data services
OSF services that provide access to collections of data in repositories and databases. Resources accessible by Data Services can generally be referenced by a name (identity, address, etc). Given a name, Data Services can then find the resource. Examples include: Feature Access Services (FAS), Coverage Access Services (CAS) and Sensor Collection Service (SCS).
data transfer
Source: OpenGIS Guide
"In the geoprocessing world, this refers to converting geodata from one (usually proprietary) data format to another. The OpenGIS Specification is not a data transfer standard. Instead, it (in most cases) specifies interfaces by which software systems can exchange information about features, geometry, spatial referencing, and geoprocessing operations. It enables remote GIS systems, for example, to behave like extensions of your local computing environment. "
data transfer standard
A (usually vector) data format designed to be a "lowest common denominator" for multiple data formats, to enable data to be used by different GIS systems.
data update cycle
Source: GETIS glossary
Data update interval
dataset series
Source: ISO 19115; ISO 19113; ISO 19114
Collection of datasets sharing the same product specification
datum
Defines the origin, orientation and scale of the coordinate system and ties it to the earth, ensuring that the abstract mathematical concept 'coordinate system' can be applied to the practical problem of describing positions of features on or near the earth's surface by means of coordinates.
DBF
Data Base File - the dBase file format
DBMS
Database management system. DBMS sometimes refers to the software that contains and organizes the data, and sometimes refers to an organizational plan for the use of information within a single project, or within one unit or the whole of an organization.
DCP
Distributed Computing Platform
de facto standard
Source: OpenGIS Guide
"A standard that has been informally adopted, often because a particular vendor was first to market with a product that became widely adopted. MS-DOS and Microsoft Windows are examples. "
de jure standard
Source: OpenGIS Guide
"An official standard created in a formal `juried` process, such as the International Organization for Standards Technical Committee 211 (ISO TC/211), which is working on problems similar to those addressed by the OpenGIS Specification, but at a higher, more abstract level."
DEM
Digital elevation model, a data exchange format developed by the United States Geological Survey for geographical and topographical data.
DEMTS
Digital and Electronic Maps Transfer Standard. Interchange of digital maps. Russian state standard GOST R*50828-95Â
DGN
DesiGN file, the Microstation drawing format
Dictionary Model
Source: The OpenGIS® Abstract Specification Topic 6: The Coverage Type and its Subtypes Version 6. http://www.opengis.org/techno/abstract/00-106.pdf
The general model for representing online dictionaries that pertain to well-known types of classification schemes and dictionaries.
DIGEST
(Digital Geographic Exchange Standard) Standard that supports images and gridded data in alignment with the ISO/IEC 1/SC 24 BIIF standard. DIGEST Annex D, known as the Image Interchange Format, is an encapsulation of the NATO Secondary Imagery Format (NSIF), which allows for the standard exchange of image, graphic and text data.
Digital Cartographic Model
Source: http://www.eurogeographics.org/Projects/GDDD/GDDD/lists/products.htm#52
"Simple digital maps having a 'flat' data structure, e.g. digitized maps. Digital Cartographic Models (DCMs) are suitable for display and plots purposes. In the context of GIS the DCM may be used as background information. The geometric form of the DCM is vector"
Digital Elevation Model
Source: http://www.eurogeographics.org/Projects/GDDD/GDDD/lists/products.htm#52
"The Digital Elevation Model (DEM) only contains elevation data. Normally, the height data are arranged in a matrix. Also, vector based contour lines and spot elevations are considered as DEM. "
Digital Landscape Model
Source: http://www.eurogeographics.org/Projects/GDDD/GDDD/lists/products.htm#52
"A Digital Landscape Model (DLM) is an object orientated topographic database. The data structure facilitates spatial analysis and linkage of geographic objects to external data. The geometric form of the DLM is vector. The DLM often contains explicit or implicit topological information. The objects, their attributes and the relations between the objects are referred to in terms of real world entities. "
digital orthoimages
Orthorectified images produced using photogrammetric techniques to orthorectify scans of aerial photos and paper maps.
digitize
The process of converting information into the digital codes stored and processed by computers. In geographic applications, digitizing usually means tracing map features into a computer using a digitizing tablet, graphics tablet, mouse, or keyboard cursor.
DIPR
See Draft Interoperability Program Report.
Directory Model
The general model for representing online, well-known types of directories (e.g. Yellow Pages).
directory service
A network-accessible service that provides access to an online directory (e.g. Yellow Pages) to find the location of a specific or nearest place, product or service.
discipline
A particular area of study, such as forestry, hydrology, disaster management, etc. Disciplines often show overlaps in their study topics, data domains and application domains
Discussion Paper
A document containing discussion of some technology or specification area prepared by a SIG or WG for release for the public. Discussion Papers are not the official position of the OGC and contain a statement to that effect.
Distributed Computing Environment (DCE)
DCP being developed by the Open Software Foundation (OSF).
Distributed Computing Platform (DCP)
The foundation technology that enables access to and exploitation of physically distributed information and services. Examples include CORBA, COM/OLE, SQL, Java, and Internet services from the World Wide Web Consortium (W3C) such as HTTP, SOAP and XML.
diversity
The ability of a system or components of a system to support multiple behaviors, functions, and data types.
DLG
Digital line graph, a form of digital map developed by the United States Geological Survey. DLGs supply users with the digital version of information printed on USGS topographical quadrangle maps.
domain
System context: A class of systems that have similar requirements and capabilities. Application context: The body of knowledge defining the range and scope of an application in terms of elements, rules and behaviors.
Draft Interoperability Program Report (DIPR)
A DIPR is an informational report written by participants from an Interoperability Program Initiative. DIPR documents may be submitted to the OGC TC for review and comment. Depending on the desired outcome, the document type should be either "Information-Only" or "Draft Discussion Paper". The former, obviously, is intended for information only and is not to be considered for public release. The latter, is intended for consideration for public release as a Discussion Paper. A DIPR does not represent the official position of the OGC nor is it an adopted OGC specification.
DTM
Digital terrain model, a method of transforming elevation data into a contoured surface of a three-dimensional display.
DXF
"Drawing eXchange Format", an AutoCad export file. Drawing interchange format, a file exchange format developed by Autodesk Inc. for its AutoCAD drafting software. DXF files are ASCII records of all objects in a drawing file. DXF is used by GIS systems for exchanging map files.
dynamic segmentation
Points along a line that vary in value, e.g. pavement thickness along a road centerline.
Glossary: 
OGC Glossary

Glossary of Terms - C

Definitions: 
CAD or CADD
Computer-aided design and drafting. CAD systems are used to create maps and plans and are closely related to GIS systems. Although most CAD systems lack certain features essential to GIS analysis, such as the power to manage different spatial coordinate systems and database capabilities, many CAD systems have been developed into full GIS with the addition of necessary functions.
cadastral survey
The means by which private and public land is defined, divided, traced, and recorded. The term derives from the French cadastre, a register of the survey of lands and is, in effect, the public record of the extent, value, and ownership of land for purposes of taxation. Cartesian Coordinates are a system of positional reference in which location is measured along two or three orthogonal (perpendicular) axes. Every location can be defined uniquely by its X, Y, and Z coordinates. Locations in the coordinate system can be established using any unit of measurement such as meters, feet, or miles.
Call for Communities
An OGC invitation to local, state, or national government agencies; transnational organizations; academic groups; or private sector companies involved in geospatial technologies to participate in a series of hands-on, collaborative engineering efforts (Pilot Projects) to test the effectiveness of new standards which support Web-based sharing and use of geospatial information.
capabilities document service profile
The result of invoking the "Get Capabilities" operation on a service is a message containing a "capabilities document" describing the service. Provides a high-level description of a service instance and its provider. Includes: a human readable description of the service, a specification of the functionalities that are provided by the service and a set of functional attributes that provide additional information and requirements about the service.
Capabilities XML
Service-level metadata describing the operations and content available at a service
Cartesian coordinates
Coordinates that differ from latitude-longitude coordinates in that the latter comprise a spherical (rather than planar) reference system.
catalog
A collection of entries, each of which describes and points to a feature collection. Catalogs include indexed listings of feature collections, their contents, their coverages, and other metadata. Registers the existence, location, and description of feature collections held by an Information Community. Catalogs provide the capability to add and delete entries. At a minimum Catalog will include the name for the feature collection and the locational handle that specifies where this data may be found. The means by which an Information Community advertises its holdings to members of the Information Community and to the rest of the world. Each catalog is unique to its Information Community.
catalog services
One thing that the OpenGIS Abstract Specification defines is a standard set of services to support on-line catalogs of geodata and geoprocessing capabilities accessible to users in networked environments. Currently, your Web browser can ask a Web indexing service such as Lycos or Alta Vista to report Web sites that contain certain text strings or combinations of text strings. OpenGIS conformant catalog services will enable our Web browser (or other software) to report Web sites (or perhaps non-Web network resources) that contain certain data themes for certain geographic areas for certain time frames. These services will also be able to report geoprocessing resources available on remote servers. Of course, you may not be the one doing the asking. Car computers, for example, will automatically use catalog services to obtain current information about road and traffic conditions.
CEN
Source: PreANVIL Glossary http://www.anvil.eu.com/find/Glossary-english.htm
European Committee for Normalization: makes standards for Europe, cooperates with ISO to avoid competition. http://www.cenorm.be/
centroid
The term given to the center of an area, region, or polygon. In the case of irregularly shaped polygons, the centroid is derived mathematically and is weighted to approximate a sort of `center of gravity.` Centroids are important in GIS because these discrete X-Y locations are often used to index or reference the polygon within which they are located. Sometimes attribute information is `attached,` `hung,` or `hooked` to the centroid location.
CIPI
CIPI is an OGC Interoperability Initiative to help organizations publish, discover, access, exchange, and maintain vital geo-spatial information and online geoprocessing services required to support critical infrastructure protection.
CITE
The OGC Conformance & Interoperability Testing & Evaluation Initiative (CITE) is an OGC Interoperability Initiative designed to test and evaluate OGC Interfaces and products that implement them. The CITE Initiative has three focus areas related to the establishment of a successful and robust OGC Conformance and Interoperability Test and Evaluation Program: * Planning and Feasibility Study, * Conformance Engine, Scripts and Guidelines, and * CITE Portal and Reference Implementations.
classification scheme
An arrangement or division of objects into groups based on characteristics that the objects have in common, e.g., origin, composition, structure, application, function, etc. It is a set of concepts, organized in some specified structure, limited in content by a scope, and designed for assigning objects to classes (concepts) defined within it ISO 11179. It helps to organize the contents of a registry and supports more meaningful queries.
clearinghouse
Source: GETIS glossary
"In general a clearinghouse provides a central access point for value-added topical guides which identify, describe, and evaluate Internet-based information resources. In our case a clearinghouse is a decentralized system of servers located on the Internet which contain field-level descriptions of available digital spatial data. This descriptive information, known as metadata, are collected in a standard format to facilitate query and consistent presentation across multiple participating sites. A clearinghouse uses readily available Web technology for the client side and uses standards for the query, search, and presentation of search results to the Web client. A clearinghouse provides information about who is providing which authorized geoinformation for which application."
client
A software component that can invoke an operation performed by a server.
client/server
The network computing revolution (which includes the distributed geoprocessing revolution) is based on software entities (clients) that tell other software entities (servers) to do things for them. Software clients say, `Send me this specific data from your database!` or `Tell me what Internet address contains this information!` or `Take this data and do a correlation operation on it!` In a simple sense, your word processor is a client when you click on `Save` and the word processor instructs the operating system (acting as a server) to save your file to disk. Interoperability interfaces make it possible for diverse computers to request things of each other over networks and get predictable responses.
COM
"Component Object Model, the Microsoft (MS) paradigm to connect components. MS has implemented the base technology for COM on the NT platform. Software AG has ported these on MVS and UNIX. A COM-object defines its interfaces. Components from different machines can be combined using DCOM ."
Common Object Request Broker Architecture (See: CORBA)
 
Communications Service Interface (CSI)
The interface by which an application platform accesses external entities which provide data transport services. The service provided is data transport among application platforms.
component
In the context of distributed computing, a component is a software program unit that performs one or more functions and that communicates and interoperates with other components through common interfaces.
componentware
Software that exists in relatively small modules with standard interfaces. Components can be combined easily to create tailored applications that are easier to maintain and upgrade than `monolithic` applications that provide the same functionality. Another benefit is that components from different vendors can be used together to provide flexible, economic solutions. componentware can be defined as software products constructed using object technology.
composite curve
Sequence of Curves such that each curve (except the first) starts at the end point of the previous curve in the sequence. (see OGC Abstract Specification (Topic 1) clause 7.3.10.4)
composite map
Two or more maps with the same geographic extent and coordinate reference system can be accurately layered to produce a composite map.
computational viewpoint
Viewpoint in RM-ODP concerned with the functional decomposition of the system into a set of services that interact at interfaces. This viewpoint captures the details of these components and interfaces without regard to distribution. (See the ORM for further definition.)
computer architecture
The functional composition of a system and its components, the interfaces between components, and interfaces with the external environment, including users and other systems.
computer environment
The general term describing the people, hardware, software, and databases comprising a single computer system or several network-connected computer systems, and the associated standards.
conceptual architecture
A diagram and accompanying text that provides a model of how a system works
conceptual schema
Base schema. Formal description of the model of any geospatial information. Application schemas are built from conceptual schemas.
Conformance Test Suite and Guidelines
The set of materials, defined under the OGC Conformance Testing Program document (available at http://www.opengeospatial.org/compliance ), required to test an implementation for conformance to a specification. (Conformance Test Suite and Guidelines refer to OpenGIS Implementation Specifications.) A software vendor whose software implements interfaces based on OGC`s standards can claim that a product "implements" particular OpenGIS Specifications. If the product has passed a conformance test for a particular OpenGIS Specification, the vendor can claim that their product conforms to that version of a specification and they can use OGC`s trademarks to assure buyers of the veracity of those claims.
connectivity
A topological property relating to how geographical features are attached to one another functionally, spatially, or logically. In a water distribution system, connectivity would refer to the way pipes, valves, and reservoirs are attached, implying that water could be `traced` from its source in the network, from connection to connection, to any given final point. Functional, spatial, and logical connectivity are examples of relationships that can be represented and analyzed in a GIS database.
container
Association role between topology primitives and those of co-deminsion -2 or greater. (see OGC Abstract Specification (Topic 1) clause 7.3.10.4)
content standard
A standard data model
conversion
The process of transferring data derived from existing records and maps to a digital database. Conversion is a major input problem and can consume the greatest share of time in a GIS project.
coordinate conversion
A mathematical operation on coordinates that does not include a change of datum. The best-known example of a coordinate conversion is a map projection. The parameters describing coordinate conversions are defined rather than empirically derived.
coordinate reference system (CRS)
A coordinate system that has a reference to the Earth. Consists of a coordinate system and a datum.
coordinate system
Composed of a set of coordinate axes with a known metric. The concept 'metric of a coordinate space' consists of the set of mathematical rules that defines the relationships between the coordinate values and the invariant spatial quantities between points; for example, the mathematical rules (formulae) required for calculating angles and distances between points from coordinate values and vice versa.
coordinate transformation
Source: GETIS glossary
A mathematical operation on coordinates that includes a change of datum. The parameters of a coordinate transformation are empirically derived from a dataset containing the coordinates of a series of points in both coordinate reference systems. This computational process is usually "over determined", allowing derivation of error (or accuracy) estimates for the transformation. Also, the stochastic nature of the parameters may result in multiple (different) instantiations of the same coordinate transformation.
coordinates
A tuple of ordered scalar values that define the position of a single point feature in a coordinate reference system. The tuple is composed of one, two or three 'ordinates'. The ordinates must be mutually independent and their number must be equal to the dimension of the coordinate space; for example, a tuple of coordinates may not contain two heights.
CORBA
"Common Object Request Broker Architecture: CORBA is an architecture and specification for creating, distributing, and managing distributed program objects in a network. It allows programs at different locations and developed by different vendors to communicate in a network through an `interface broker.` CORBA was developed under the auspices of the OMG (Object Management Group) and has been sanctioned by both ISO and X/Open as the standard architecture for distributed objects (also known as components)."
The basic distributed object scheme developed by the Object Management Group (OMG), a consortium similar to OGC but focused on object technology instead of distributed geoprocessing. Object Request Brokers (ORBs) help clients find servers.
core technology
The set of Implementation Specifications resulting from the Technology Development process that are based on the Abstract Specification.
coverage
Source: The OpenGIS® Abstract Specification Topic 6: Schema for coverage geometry and functions, Version 7 .
A feature that associates positions within a bounded space (its spatiotemporal domain) to feature attribute values (its range). GIS coverages (including the special case of Earth images) are two- (and sometimes higher-) dimensional metaphors for phenomena found on or near a portion of the Earth's surface. A coverage can consist of a set of features or Feature Collections. Earth images are seen as Grid Coverages that contain features whose geometries are of type "set of cells" or "set of pixels" (surfaces).
coverage domain model
The definition of a domain-specific application schema for a well-known geospatial coverage. For example: DTED.
Coverage Model
Source: The OpenGIS® Abstract Specification Topic 6: The Coverage Type and its Subtypes Version 6. http://www.opengis.org/techno/abstract/00-106.pdf
The basic model for how earth information may be represented as raster or grid coverages (e.g., an image or digital terrain model).
critical infrastructure
Critical infrastructure encompasses large-scale systems in a range of sectors - energy, tele-communications, transportation, public health services, banking, government, public safety etc. These systems are essential to maintaining society.
curve
1-dimensional geometric primitive, representing the continuous image of a line (see OGC Abstract Specification (Topic 1) clause 6.3.16)
curve segment
1-dimensional geometric object used to represent a continuous component of a curve using homogeneous interpolation and definition methods. (see OGC Abstract Specification (Topic 1) clause 6.3.17)
Glossary: 
OGC Glossary

Glossary of Terms - B

Definitions: 
backward (and forward) compatibility
A new version of a standard is backward compatible if all implementation of the new standard include the conformance requirements of the previous versions of the standard.
base document
The working draft of the OpenGIS Specification, maintained by the Chairman of the OGC Technical Committee, which is the repository for working papers that have been submitted by Committee members.
base maps, data, or layers
Spatial data sets that provide the background upon which more specific thematic data is overlaid and analyzed. As inputs into a GIS, the term base map is usually applied to those sources of information about relatively permanent features including topography, soil data, geology, cadastral divisions, and political divisions. Within a GIS database, such information may become part of a land base to which other information is indexed and referenced.
base standard
An approved International Standard, Technical Report, CCITT Recommendation or National Standard.
bind
In the context of OGC Web Services, Bind refers to Web service components connecting and executing through interfaces
BMP
Bitmap. A Microsoft Windows image format.
bounding box
a set of 2, 4, 6 or 8 numbers indicating the upper and lower bounds of an interval (1D), rectangle (2D), parallelpiped (3D), or hypercube along each axis of a given CRS
broker
A kind of intermediary service whose responsibility is only to bring other services together (typically a service requester and a service provider) and has no responsibility for satisfactory completion of the `contract` established between the requester and provider.
business object
An identifiable business concept such as customer or order.
business process
See process domain model.
Glossary: 
OGC Glossary

Glossary of Terms - A

Definitions: 
Abstract Data Type
The basic information construct used by the GeoMobility Server and associated Core Services. Consists of well-known data types and structures for location information. Defined as application schemas that are encoded in XML for Location Services (XLS).
accuracy
Source: OpenGIS Guide
The degree to which information on a map or in a digital database matches true or accepted values. Accuracy pertains to the quality of data and the number of errors contained in a dataset or map. In discussing a GIS database, it is possible to consider horizontal and vertical accuracy with respect to geographic position, as well as attribute, conceptual, and logical accuracy. The effect of inaccuracy and error on a GIS solution is the subject of sensitivity analysis. Accuracy, or error, is distinguished from precision, which concerns the level of measurement or detail of data in a database.
agent
Source: OpenGIS Guide
A kind of intermediary service which acts on behalf of another service (service provider or requester) according to rules established upon its invocation. Also known as an `intelligent agent.`
Annual Technical Baseline Target
The Annual Technical Baseline Target is the subset of the elements of the Technical Plan that are scheduled to be completed within any given calendar year.
ANSI
An abbreviation for American National Standards Institute. ANSI standards have been established for many elements of computer systems to aid research and development. The existence of standards allows designers to develop general solutions to common problems.
applet
A small application, with limited functionality, designed to operate in a componentware and/or middleware environment. Large, multifunctional, `monolithic` applications can be, and in the future often will be, broken into single-function applets that interoperate with other applets, and that can be assembled, perhaps only temporarily, into a user`s work environment. Java applets, for example, are typically downloaded via the Internet into your computer`s program memory, where they accomplish their task (such as `let the user zoom on this geodata`) and then `evaporate`.
application
Source: OpenGIS Guide
The use of capabilities, including hardware, software and data, provided by an information system specific to the satisfaction of a set of user requirements. See Geographic Application and Geoprocessing Application.
application assembly
Assemble single application from components
application developer
Source: OpenGIS Guide
A software programmer who creates applications, usually by integrating a variety of pre-existing elements such as application programming interfaces and software and hardware platforms.
application domain models
Application-oriented models that characterize information and service resources within a domain. They are often based upon a General Model and must always be consistent with the Abstract Model. The two subclasses are: Data Domain Models and Process Domain Models.
application integration
Integrate multiple applications to support a cross function business process
application platform
Source: OpenGIS Guide
The collection of hardware and software components that provide the infrastructure services used by application programs. APIs make the specific characteristics of the platform transparent and accessible to the application.
application profile
Source:  ISO 19101, ISO 19106
A set of one or more base standards and - where applicable - the identification of chosen clauses, classes, subsets, options and parameters of those base standards that are necessary for accomplishing a particular function.
Application Programming Interface (API)
An interface definition that permits invoking services from application programs without knowing details of their internal implementation.

Application Programming Interface (API)
An interface definition that permits invoking services from application programs without knowing details of their internal implementation.
application schema
A set of conceptual schema for data required by one or more applications. An application schema contains selected parts of the base schemas presented in the ORM Information Viewpoint. Designers of application schemas may extend or restrict the types defined in the base schemas to define appropriate types for an application domain. Application schemas are information models for a specific information community.
application services
OWS Services operating on user devices or servers that have network connectivity. Users use Application Services to access Registry, Portrayal, Processing and Data Services. Application Services commonly, but not necessarily, provide user-oriented displays of geospatial content and support user interaction at the user terminal.
application software
Source: OpenGIS Guide
The computing elements supporting users` particular needs. Frequently includes data, documentation, and training, as well as programs.
architectural framework
Source: OpenGIS Guide
Identifies key interfaces and services, and provides a context for identifying and resolving policy, management and strategic technical issues. Constrains implementation by focusing on interfaces, but does not dictate design or specific technical solutions.
architecture
An abstract technical description of a system or collection of systems. Modern software architectures employ interoperability interfaces to enable enterprises and whole industries to establish coherent, flexible, integrated information flows that can be implemented with heterogeneous but intercommunicating software systems. The OpenGIS Specification defines the interoperability interfaces that make it possible to include geographic information in these information flows. Conceptually based, architecture does not contain the level of detail needed for construction.
area of interest
A user defined area (represented by a bounding box, circle or polygon). Often used as a filter in a query.
ASCII
Source: OpenGIS Guide
An abbreviation for American Standard Code for Information Interchange. The ASCII format provides computer systems with a common language for exchanging information. Although most GIS software system make use of proprietary binary codes, almost all systems have import-export capabilities for translating between ASCII and binary formats.
asynchronous
Calling application does not require immediate response to request before proceeding
attribute data
Source: OpenGIS Guide
Descriptive information about features or elements of a database. For a database feature like census tract, attributes might include many demographic facts including total population, average income, and age. In statistical parlance, an attribute is a `variable,` whereas the database feature represents an `observation` of the variable.
Glossary: 
OGC Glossary

Glossary of Terms

The OGC works in the complex and specialized area of software engineering that concerns itself with the attributes and geometries of features and phenomena on or near the Earth's surface, and with the many kinds of digital processing employed to make this data useful. To enable efficient and precise communication, every specialty, including this one, has its own special terms and special definitions of ordinary words. Facilitating agreement on definitions of geospatial technology terms - for the sake of "semantic interoperability" - is appropriately part of OGC's mission.

Special Interest Groups

Special Interest Groups (SIG) provide a forum for the discussion of business and technology interoperability requirements for given geographic region or information community.

Name space Lead **
** - There may be Co-Chairs or Vice-Chairs that are not listed in this table

Domain Working Groups

Domain Working Groups (DWG or WG) provide a forum for discussion of key interoperability requirements and issues, discussion and review of implementation specifications, and presentations on key technology areas relevant to solving geospatial interoperability issues.

Subcommittees

A Subcommittee is a standing group (organizationally, a subgroup of the Technical Committee or the Planning Committee) of individuals composed of members of the TC or PC and Invited Guests, with a mission to provide recommendations to the TC or PC in some general area. A Subcommittee does not generate a Standard nor do they work on a Standard.

Pages