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The terms and acronyms listed in this glossary have been deliberately selected with a bias towards terms associated with GIS, i.e. rather than to any terms which might be used in the fisheries management field. In some instances acronyms have not been listed here - this is when they simply appear once as part of a table or list, e.g. as a list of GIS supporting organizations, or when they form the name of a software product or a particular purpose built software system, or where they form the name of a company.

2.5-DA dimensional system in which height or depth is tied to the surface plane.
Active sensorA sensing device which illuminates an object with its own radiation source and then captures the echo received.
AESAtmospheric Environment Service.
AGIAssociation of Geographic Information. A UK based umbrella association coordinating the GIS industry and activities in Britain.
AlgorithmA procedure for performing a specific action; or a set of instructions to the computer which provide a guaranteed solution to a specific task.
AlphanumericConsisting of both letters and numbers.
AnnotationThe alphanumeric text or label appended to a map.
AreaA bounded, continuous two dimensional surface which may include its boundary. Usually defined in terms of an external polygon or a set of grid cells.
ASCIIAmerican Standard Code for Information Interchange; an 8 bit coding system used to represent alphanumeric characters in computers.
AttributeAny non-spatial characteristic of an object.
Autonomous GPSThe receipt of information from a single global positioning satellite about the location of the receiving device. In this case the result would not be very accurate, i.e. typically only to the nearest 100 metres.
AVHRRAdvanced Very High Resolution Radiometer.
BDRMRegional Maritime Database; of West African countries.
BenchmarkA series of exercises which may be given to a software company by a prospective GIS purchaser, in order to see how well the particular software can perform a range of tasks.
BinaryA number system which uses the base 2 and has only the digits 0 and 1.
BitIn digital computing, a binary digit; the smallest element of information.
BMFDBritish Marine Fishes Database.
BODCBritish Oceanographic Data Centre.
Boolean logicThe use of certain operators in a command given to a computer, e.g. such as “AND” or “NOT”, so as to show the sort of conditions which need to be met before the command is carried out.
BPIBits Per Inch; a measurement of linear data density on magnetic storage materials such as tape.
BufferA uniform unit of area around an object.
ByteUnit of digital data, usually that required to store a single character, typically eight bits.
CADComputer Aided Design.
CadastralConcerned with property ownership, particularly for taxation purposes.
CartographyThe science and practice of representing the features of the Earth's surface graphically (in map form).
CASICompact Airborne Spectrographic Imager; a sensor used to determine the spectral signatures of objects on the Earth's surface.
CCTComputer Compatible Tape; magnetic tape containing data in computer readable digital format.
CD-ROMCompact Disk - Read Only Memory.
CDTConductivity/Salinity, depth and temperature recorder.
CECAFFishery Committee for the Eastern Central Atlantic.
CGISCanadian Geographic Information System; one of the earliest GIS installations.
ChoroplethMapping type which is based on unit areas of equal value.
ConnectivityA relative measurement of how well a settlement is connected to other settlements by, for instance, any transport network.
ContiguityThe relative degree of adjacency between neighbouring areas.
CoordinateA set of numeric quantities that designate position in a given reference system.
COWLISCoastal Ocean Water Level Information System.
CPUCentral Processing Unit; that part of the computer which is responsible for numerical calculations and control.
CPUECatch Per Unit of Effort.
CRTCathode Ray Tube.
CSIROCommonwealth Scientific and Industrial Research Organisation (Australia).
CZCSCoastal Zone Colour Scanner.
DATDigital Audio Tapes.
DataA general term which may describe numbers, characters or groups of bits suitable for processing by a computer.
DatabaseA collection of related observations or measurements held within the computer.
Data captureThe creation of digital data from existing information sources.
Data loggerAn automatic or semi-automatic device used to collect and record data.
Data modelThe rationale for a particular data organisation scheme within a database.
Data structureOrganisation adopted for the data held in a digital database.
DBMSDatabase Management System; software to control the storage and retrieval of integrated data holdings.
DEMDigital Elevation Model (see DTM).
DFODepartment of Fisheries and Oceans.
DFONETDepartment of Fisheries and Oceans Ocean Information System.
DifferentialThe use of two or more global positioning GPS satellites as a means of determining an exact location on the Earth's surface, i.e. by giving a latitude and longitude coordinate reference with an accuracy of about one metre.
Digital mapA map which can be displayed on a computer screen using previously digitised data.
Digital numberThe numerical value of a specific pixel.
DigitiserA device which converts analog information into a digital format. The device is commonly used to transform graphical (mapped) information into digital format.
DIPDocument Image Processing.
DirectoryA collection of information about whole datasets.
Disk driveThe basic storage device of a computer system.
DistributedWhere computers, and especially databases, are computing linked in a wide area network so as to take advantage of distant databases.
dpiDots per inch.
DTM(i)Digital Terrain Model; a digital representation of relief. Usually a set of elevation values incorrespondence with a grid cell. (ii) Desk Top Mapping; the inception of simple GIS techniques into normal business computing practices.
E-MailElectronic Mail; the communications system whereby messages can be sent from one computer to another with the use of networking.
ECDISElectronic Chart Display and Information System.
Edge matchingThe process of ensuring that data along the adjacent edges of map sheets matches, i.e. in terms of both position and attributes.
EEZExclusive Economic Zone.
EMRElectromagnetic radiation.
EOSATEarth Observation Satellite.
EPAEnvironmental Protection Agency.
ERS-1The first Earth Resources Satellite, launched by the European Space Agency.
ESAEuropean Space Agency.
ESISEuropean Seabed Information Service.
ESRIEnvironmental Systems Research Institute; the software house which produces Arc/Info GIS.
False coloursThe assigning of arbitrary colours to data values in a remotely sensed image.
Feature codeAn alphanumeric code which describes and/or classifies geographic features.
FFISForeign Fishery Information System.
FieldA subdivision of a record which contains one unit of information, e.g. the answer to a single question.
FileA collection of related information stored in a computer; often part of a database.
FormatThe physical organisation of data elements within a dataset.
FOVField of View: the angle through which a sensing instrument is sensitive to radiation.
GEBCOGeneral Bathymetric Chart of the Oceans.
GeneralisationThe smoothing of lines on a map so that the outline becomes less complex, or the simplification of the image of a map as for instance occurs when scale changes are made from large to small.
GENIEGlobal Environmental Network for Information Exchange.
GeocodingAllocating a code to represent the spatial characteristics of an entity.
GeodesyThe branch of mathematics which is concerned with making accurate measurements of large portions of the Earth's surface.
GeomaticsThe complete geographical information technologies.
Geo-referenceThe grid coordinate allocated to a particular location as a means of linking an object with that location.
GeostationaryA satellite which orbits above the equator at Satelliteapproximately 36 000 kms, such that its period of revolution about the Earth matches the Earth's rotational speed.
GeostatisticsA branch of statistics which is concerned with the mathematics of spatial surfaces.
GFCMGeneral Fisheries Council for the Mediterranean.
Gigabyte1000 megabytes.
GISGeographic(al) Information Systems; the hardware and software systems necessary for capturing, storing, editing, integrating, manipulating, analysing and displaying spatially referenced data.
GISCOGeographic Information Systems of the European Community.
GISTGeographical Information Systems Tutorial; a GIS training software package.
GISTARSGeographic Information STARter System; a GIS training package.
GPSGlobal Positioning System; a set of satellites which transmit signals which can be decoded by receivers to determine positions anywhere in the world.
Graphical dataData which can be used to create a graphical representation of objects in the real world, i.e. data referring to the outlines on a map.
GRIDGlobal Resources Information Database (of the United Nations Environment Programme).
Ground truthThe information gathered about the Earth's surface at the same time as a satellite pass is made, i.e. in order to interpret and calibrate remotely sensed observations.
GUIGraphical User Interface: a computer user interface which makes use of graphical objects, such as icons, for the selection of options, and usually has a windowing capability enabling multiple windows to be displayed on the screen.
HardwareThe physical equipment in a computer system.
HMMRHigh-resolution Multifrequency Microwave Radiometer.
HOHydrographic Office (in the UK).
ICCATInternational Commission for the Conservation of Atlantic Tunas.
ICESInternational Council for the Exploration of the Seas.
ICLARMInternational Center for Living Aquatic Resources Management.
ICOINInland Waters, Coastal and Ocean Information Network.
IDIASIce Data Integration and Analysis System.
IFMIntegrated Fisheries Management.
IFOVInstantaneous Field of View; a term used to describe the ground resolution of a remote sensing scanner.
Image analysisThe transforming and interpretation of remotely sensed digital data, with the help of special hard- and software systems.
InmarsatA new series of communication satellites which will be used by global positioning systems to give highly accurate locations on the Earth's surface.
InteractiveThe operation of a computer system through processing continual, instantaneous communication between the operator and the machine.
InternetAn international computer communication system over which information is distributed.
IOCIntergovernmental Oceanographic Commission (of the United Nations Educational, Scientific and Cultural Organization)
IsolinesLines on a map which join places having equal values, e.g. contour lines.
IsotropicPertaining to surfaces on the Earth which are uniform in all directions.
ITInformation Technology.
ITQIndividual Transferable Quota.
JANETJoint Academic Network; a UK computer network linking academic and research sites.
KilobyteOne kb = 1024 bytes.
KrigingA spatial interpolation technique which was originally developed in the mining industry.
LANLocal Area Network; the linking of computing systems, usually within a single department.
LandsatA series of US polar orbiting satellites, first launched in 1972 by NASA, which carry both the multispectral scanner and thematic mapper sensors.
LayerA subset of digital map data which contains information all relating to one subject, e.g. water quality or the coastline.
LineIn GIS it is sometimes called an arc, a link or a segment. It is a line segment which directly links two points (nodes) on a map.
LISLand Information Systems; a GIS for land resources management and an acronym given to some early GIS's.
LivewareThe name sometimes given to the personnel who operate computer systems.
LMELarge Marine Ecosystem; areas of the sea having unified hydrographic regimes and trophically related marine populations.
MARISMarine Information Service.
MARSISMarine Remote Sensing Information System.
MCBMarine Catchment Basin.
MEDSMarine Environmental Data Service.
MegabyteOne Mb = 1,048,576 bytes.
Meta databaseA database which gives details about all the datasets which make up any database, e.g. date when data was gathered, source of data, format of data, etc.
MicrocomputerA small stand-alone computer processing unit.
MODEMA MOdulator-DEModulator: a digital device which allows computers to communicate with each other via the telephone network.
MosaicA map or satellite image, compiled from several different images.
MSSMultiSpectral Scanner; a remote sensing device that records electromagnetic energy in several wavelength bands simultaneously.
MultimediaThe use of text, data, still and motion video, sound and computer graphics by a software programme to form a composite display.
NAFONorth Atlantic Fisheries Organisation.
NCGIANational Center for Geographic Information and Analysis: a US research center for GIS.
NCICNational Cartographic Information Center.
Network(i) The physical configuration of cables, hard- and software allowing for communication between computers at different locations. (ii) The data structure for route diagrams, shortest path analysis, etc.
NetworkingThe use of a computer plus a MODEM link to obtain access to remotely held databases.
NimbusA series of US Earth observing experimental weather satellites which carried a variety of sensors, the last of which was launched in 1978. They are now non-operational.
NLRNational Aerospace Laboratory; a Dutch distributor of remote sensing products.
NOAANational Oceanographic and Atmospheric Administration.
NODCNational Oceanic Data Center.
NodeThe start or end of a link or line; a point which can be shared by several lines.
NOSNational Ocean Service.
NRSCNational Remote Sensing Centre.
NTFNational Transfer Format. The UK standard for the transfer of geographic digital data - it has now become a British Standard (BS7567).
NWINational Wetland Inventory.
ObjectComputer programmes which use object oriented oriented techniques and languages. These employ a programming data centred approach to programming, based on the definition of “objects”.
OCMOcean Color Monitor.
OctreeA representation for compressing data which is geo-referenced in 3- D (using voxels).
ODESOcean Data Evaluation System.
OperatingThe high-level administration programme running system in a computer at all times, i.e. to control all the operations and tasks, e.g. MS-DOS and UNIX.
Optical diskA data storage device having a disk whose coating can be altered to encode information. Data is read from the disk by means of a laser.
OrthophotoA photograph which has been manipulated so as to eliminate image displacement due to photographic tilt and relief.
OSOrdnance Survey (Great Britain).
OverlayA set of graphical data which can be superimposed on to another set of graphical data. Sometimes used as a synonym for layer.
PackageA generalised programme capable of performing several operations and covering the requirements of many users.
Passive sensorA device which captures and records natural radiation reflectance levels.
PeripheralAny hardware device added to a computer system.
PhotogrammetryThe technique of obtaining precise measurements from images.
PixelFrom Picture Element: the smallest unit whose characteristics may be uniquely determined; an individual dot on the screen.
PlatformIn remote sensing, the physical object which carries the sensors that make the remote measurements.
PlotterA device used to record information, such as maps or graphs, on paper or film. They are usually based on one or more pens which move over the medium under control of a computer.
Polar orbitingThe path of most orbiting satellites, i.e. those which circumnavigate the Earth about 15 times per day and which pass almost over the poles on each orbit.
PolygonA closed, two dimensional figure with three or more sides and intersections, e.g. a geographic area such as a field or other land unit.
PreprocessingThe manipulation of data, via a large number of techniques, to make it suitable for further manipulations or analysis.
Primary dataData which has been directly gathered from real world situations by surveys, questionnaires, measurements, etc.
ProgrammableAny computing or data recording device which can be pre- programmed to carry out any desired functions.
ProjectionThe systematic construction of features (physical and political) on a plane surface to represent corresponding features on a spherical surface.
ProtocolIn data communications, a set of rules which determine the formats and conventions by which information may be exchanged between different systems.
Push broomAn airborne sensor which functions by taking sensorcomplete frames (pictures) of any scene over which it passes.
QuadtreeA spatial data structure based on successive subdivision of an area, the purpose of which is to minimise data redundancy.
RadiometerA passive device for intercepting and quantitatively measuring electromagnetic radiation in a band of wavelengths.
RAMRandom Access Memory; a type of chip based memory which a computer processor can read data from and write data to.
RasterA format for storing, processing and displaying graphic data in which graphic images are stored as values for uniform grid cells or pixels.
RDBMSRelational Database Management System: a widely used strategy for data organisation in GIS software.
RecordA collection of related fields, e.g. all the responses from one questionnaire.
RegistrationThe superimposition of locations on one image with the corresponding locations on a second image or map.
Remote sensingObtaining information about an object or phenomenon without any direct contact, e.g. via the use of satellite sensors or Radar.
ResolutionThe minimum size of a feature which can be reliably distinguished by a remote sensing system.
RESTECRemote Sensing Technology Center.
ROMRead Only Memory; a type of chip based memory which a computer processor can read data from but cannot write data to.
RubberA GIS process that geometrically adjusts map sheeting features to enable a digital map to fit a designated base.
Run-lengthA method of digital coding which saves on the encoding amount of data which needs to be stored.
SARSynthetic Aperture Radar; a radar system based on a series of elemental antenna units, or sequences of observations from a single antenna, from which the effective antenna is mathematically constructed through signal processing.
ScannerA device used to capture data digitally from a paper map or other graphic representation.
SeasatA polar orbiting, earth observation satellite designed to gather information about the oceans. Although the satellite only operated in 1978, much of its synthetic aperture radar data is still useful.
SeaWIFSSea-viewing Wide-Field-of-View Sensor.
Secondary dataData which has been acquired from previously published sources.
SensorA device that gathers electromagnetic radiation or other physical data and presents it in a form suitable for obtaining information about the environment.
SignatureA set of spectral, tonal, temporal or spacial characteristics that together serve to identify a class or feature by remote sensing.
SoftwareA computer programme written in a high or low level language.
Spaghetti dataA simple vector data structure comprising feature codes and co- ordinates without any topology.
Spatial dataData or information describing the geographical position or location of an object.
SpectralTypical radiation reflectance values as given signatures off by different ground or water surfaces.
SplineA mathematical formula for drawing regular function curves.
SPOTSatellite pour l'Observation de la Terre. A French multispectral remote sensing satellite system having pointable sensors, which was first launched in 1986.
SQLStructured Query Language; a query language interface for relational databases. It is used to define, access and manipulate data stored in these databases.
StandardsIn computing, the establishment of a unified set of procedures for handling digital data.
Swath widthThe area on either side of a platform which is surveyed by a remote sensing instrument.
SYMAPSynagraphic Mapping System; one of the earliest and most widely used computer mapping systems, producing crude line printer output graphics.
TACTotal Allowable Catch.
TelnetTelecommunications Network.
Thematic mapA map depicting one or more specific themes, e.g. rainfall or population density.
TINTriangulated Irregular Network; a variable resolution data structure for surface models, based on a Delaunay triangulation. It is based on a series of non-overlapping triangles which completely cover any surface.
TMThematic Mapper; a seven channel multispectral scanner sensing device, designed for monitoring the Earth's surface, and flown on the Landsat series of satellites.
TopographyThe collective features of the Earth's surface, including relief, hydrology and cultural features. The features may be accurately located on topographic maps.
TopologyA geographic data structure in which the inherent spatial connectivity and adjacency relationships of features are explicitly stored and maintained.
TransducerThat part of the acoustic sonar system which converts an electrical signal to a mechanical vibration in order to move adjacent water particles so as to cause a pressure wave.
TransformationThe ability to change from one coordinate system to another. Sometimes also called rectification.
Turnkey systemA complete computer system consisting of a hardware and software combination which has been assembled in order to perform a specified range of tasks.
UKDMAPUnited Kingdom Digital Marine Atlas.
UNCLOSUnited Nations Convention on the Laws of the Sea.
UNEPUnited Nations Environmental Program.
UniqueAn alphanumeric coding given to any object identifier which is listed in a table, which allows for its identification and allows it to be matched with other objects.
USGSUnited States Geological Survey; the organization dealing with US governmental topographic mapping.
USNOUnited States Naval Observatory.
UTMUniversal Transverse Mercator; the most frequently used (in GIS) map projection system. A series of north-south zones are established, and locations are designated in terms of distance in metres east of the western edge of the zone, and north or south of the equator.
VDUVisual Display Unit; commonly thought of as a computer screen.
VectorIn GIS, the basis for representation of spatial information in which objects are defined as either points, lines or polygons, and these are processed in terms of x,y coordinates.
VideographyThe use of video cameras on airborne platforms to capture images of the Earth.
VisualizationThe processes whereby graphical information may be perceived, i.e. any one map be interpreted differently by any two people in accordance with their inherent perceptual capabilities.
VoxelA data structure used to assign geo-references in a 3-D spatial model.
WADABAWadden Sea Data Base.
WANWide Area Network; the link up of computing systems over a wide spatial area.
WATISWadden Sea Information System.
WINSWeather Information Network System.
WOCEWorld Oceanic Circulation Experiment.
WorkstationA high performance personal computer aimed typically at scientific and technical users. It usually runs using the UNIX operating system. Most of the more powerful GIS's run on work stations.
WVSWorld Vector Shoreline.

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