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acceptable quality level (AQL)

threshold value applied to the results of testing data quality to determine whether the data meets criteria determined from a standard, specification or user requirements

aggregated AQL

acceptable quality level for aggregated results from a number of tests, e.g. 100% correct

Coordinate Reference System

a coordinate system that is related to an object by a datum [ISO 19111]


Coordinate Reference System


Catalogue Services for the Web. Http protocol request/respond binding for OGC Catalogue Service.

Note: see

Data Provider

the organisation that creates the data and supplies the data for web publication, along with its metadata.

Note: for INSPIRE data, the Public Authority with the statutory obligation under the INSPIRE regulations.

Data Publisher

the organisation that publishes the data on the web and supplies data services to data users

data resource

dataset, collection of datasets or service supplying data


identifiable collection of data [ISO 19101]

dataset series

collection of datasets sharing the same specification, e.g. a 1:1250 scale map series [ISO 19115]

discovery metadata

information about a data or service resource, used to discover and access its suitability for sharing or re-use.


Discovery Metadata Service.

Note: one of a number of business services associated with the UK Location Information Infrastructure. Implemented by the CSW interface at


set of allowable values


Document Type Definition

Note: DTD is an XML schema language which defines the legal building blocks of an XML document. It is not relevant in the context of GEMINI2 metadata instances where _XSD_ schemas are used to define the structure of XML documents.


l’Equipe D’Experts en Normalisation

Note: a collaborative workspace for standardisation in the domain of geographic information. See

enumerated list

set of values, each of which is identified by a code


European Petroleum Survey Group (defunct but the abbreviation is retained in the name of the EPSG Geodetic Parameter Dataset). Since 2005 _OGP_ Surveying and Positioning Committee.

Note: examples are given of the use of EPSG URIs in _metadata instances_. This does not imply that the EPSG registry is the _de jure_ registry of geodetic parameters for UK Location.


General Multilingual Environmental Thesaurus.

Note: developed by the European Topic Centre for the European Environment Agency.

Note: currently published and managed by the European Environmental Information and Observation Network.

Note: GEMET can be browsed and searched on-line, accessed through web services or downloaded as HTML or SKOS files, see


the UK discovery metadata profile of ISO 19115.

Note: in this document the term GEMINI2 means version 2.2 of UK GEMINI.

geographic identifier

label or code that identifies a location [adapted from ISO 19112]


Geography Markup Language [ISO 19136]


resolution in terms of density or frequency


infrastructure for Spatial Information in Europe


International Organisation for Standardisation

ISO/TC 211

The committee is responsible for standards such as ISO 19115, ISO 19136 and ISO 19139.

Notes: ISO Technical Committee 211 is responsible for standardisation in the field of digital geographic information. The home page of ISO / TC 211 is


identifiable geographic place


data about data [ISO 19115]


collection of metadata about a set of data resources

metadata element

individual item of metadata relating to a data resource, e.g. Extent, Topic

metadata instance

physically instantiated metadata.

Note: in the context of this document a metadata instance will be an _XML document_ conforming to ISO / TS 19139 and other associated standards.

metadata item

a top level metadata concept in the UK GEMINI standard. Title, for example, is a metadata item.

Note: metadata items may comprise sub-items.

metadata service

service that supplies information about data resources


identifiable set of metadata relating to a single data resource


Open Geospatial Consortium.

Note: an industry consortium of companies, government agencies and universities developing publicly available interface standards to geo-enable the Web, wireless, location-based services, and mainstream IT. See


International Association of Oil and Gas Producers


set of one or more base standards or subsets of base standards for a particular application

quality assessment

review of quality of a data resource

quality assurance

process to ensure that quality is of an acceptable level

quality control

process of checking items to ensure that they are of an acceptable level of quality

quality management

overall process for assessing and controlling quality

quality result

value of a quality measure


a language for making assertions about patterns in XML documents; ISO 19757 Document Schema Definition Language


application that provides information and /or functionality to other applications [adapted from Draft Implementing Rules for INSPIRE Transformation Services]


Spatial Reference System.

Note: a system for specifying position in the real world [ISO 19112]

UK Information Infrastructure

Infrastructure for the publication of location information as part of the implementation of the UK Location Strategy.  Incorporates the UK member state implementation of INSPIRE.

UK Location Coordination Unit

legal entity for the day-to-day coordination and management of the UK Location Information Infrastructure and the UK member state element of INSPIRE.


UK Location Information Infrastructure

universe of discourse

view of the real or hypothetical world that includes everything of interest


Uniform Resource Identifier.

Notes: URIs identify resources and may allow access to representations of the resources. A URL is a URI. An overview of W3C materials relating to address can be found at


Uniform Resource Locator. Specifies where an identified resource is available on the Web and the mechanism for retrieving it.


Coordinated Universal Time


Universally (or Global) Unique IDentifier (UUID) is a unique 128-bit integer that is represented as a 36 (or 32 ignoring the dashes) character string of hexadecimal numbers.

Note: UUIDs are system generated and ideally a UUID will never be generated twice by any computer in existence.


a Web Accessible Folder (WAF) is an HTTP accessible directory of files

Note: typically metadata files in XML format in which all files and their time-stamps are visible to a web browser or client. Crawlers are able to parse the file listings and date-time stamps and provide a search interface on these documents.


Web Mapping Service


Web Feature Service


XML Linking Language

Note: used to include metadata element data by-reference rather than by-value.

Note: the XLink specification can be found at


eXtensible Markup Language

Note: the XML specification can be found at

XML Document

a collection of data represented in XML

XML parser 

software component responsible for reading an XML document and dividing it into individual elements and attributes.

Note: parsers will check that an XML document is well-formed. Some parsers will undertake a schema validation.


XML Schema Definition language.

Note: an XSD is a document written in XML that defines the structure of an XML document.

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