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-D | A dimensional system in which height or depth is tied to the surface plane. |
| Active sensor | A sensing device which illuminates an object with its own radiation source and then captures the echo received. |
| AES | Atmospheric Environment Service. |
| AGI | Association of Geographic Information. A UK based umbrella association coordinating the GIS industry and activities in Britain. |
| Algorithm | A procedure for performing a specific action; or a set of instructions to the computer which provide a guaranteed solution to a specific task. |
| Alphanumeric | Consisting of both letters and numbers. |
| Annotation | The alphanumeric text or label appended to a map. |
| Area | A bounded, continuous two dimensional surface which may include its boundary. Usually defined in terms of an external polygon or a set of grid cells. |
| ASCII | American Standard Code for Information Interchange; an 8 bit coding system used to represent alphanumeric characters in computers. |
| Attribute | Any non-spatial characteristic of an object. |
| Autonomous GPS | The 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. |
| AVHRR | Advanced Very High Resolution Radiometer. |
| BDRM | Regional Maritime Database; of West African countries. |
| Benchmark | A 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. |
| Binary | A number system which uses the base 2 and has only the digits 0 and 1. |
| Bit | In digital computing, a binary digit; the smallest element of information. |
| BMFD | British Marine Fishes Database. |
| BODC | British Oceanographic Data Centre. |
| Boolean logic | The 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. |
| BPI | Bits Per Inch; a measurement of linear data density on magnetic storage materials such as tape. |
| Buffer | A uniform unit of area around an object. |
| Byte | Unit of digital data, usually that required to store a single character, typically eight bits. |
| CAD | Computer Aided Design. |
| Cadastral | Concerned with property ownership, particularly for taxation purposes. |
| Cartography | The science and practice of representing the features of the Earth's surface graphically (in map form). |
| CASI | Compact Airborne Spectrographic Imager; a sensor used to determine the spectral signatures of objects on the Earth's surface. |
| CCT | Computer Compatible Tape; magnetic tape containing data in computer readable digital format. |
| CD-ROM | Compact Disk - Read Only Memory. |
| CDT | Conductivity/Salinity, depth and temperature recorder. |
| CECAF | Fishery Committee for the Eastern Central Atlantic. |
| CGIS | Canadian Geographic Information System; one of the earliest GIS installations. |
| Choropleth | Mapping type which is based on unit areas of equal value. |
| Connectivity | A relative measurement of how well a settlement is connected to other settlements by, for instance, any transport network. |
| Contiguity | The relative degree of adjacency between neighbouring areas. |
| Coordinate | A set of numeric quantities that designate position in a given reference system. |
| COWLIS | Coastal Ocean Water Level Information System. |
| CPU | Central Processing Unit; that part of the computer which is responsible for numerical calculations and control. |
| CPUE | Catch Per Unit of Effort. |
| CRT | Cathode Ray Tube. |
| CSIRO | Commonwealth Scientific and Industrial Research Organisation (Australia). |
| CZCS | Coastal Zone Colour Scanner. |
| DAT | Digital Audio Tapes. |
| Data | A general term which may describe numbers, characters or groups of bits suitable for processing by a computer. |
| Database | A collection of related observations or measurements held within the computer. |
| Data capture | The creation of digital data from existing information sources. |
| Data logger | An automatic or semi-automatic device used to collect and record data. |
| Data model | The rationale for a particular data organisation scheme within a database. |
| Data structure | Organisation adopted for the data held in a digital database. |
| DBMS | Database Management System; software to control the storage and retrieval of integrated data holdings. |
| DEM | Digital Elevation Model (see DTM). |
| DFO | Department of Fisheries and Oceans. |
| DFONET | Department of Fisheries and Oceans Ocean Information System. |
| Differential | The 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 map | A map which can be displayed on a computer screen using previously digitised data. |
| Digital number | The numerical value of a specific pixel. |
| Digitiser | A device which converts analog information into a digital format. The device is commonly used to transform graphical (mapped) information into digital format. |
| DIP | Document Image Processing. |
| Directory | A collection of information about whole datasets. |
| Disk drive | The basic storage device of a computer system. |
| Distributed | Where computers, and especially databases, are computing linked in a wide area network so as to take advantage of distant databases. |
| dpi | Dots 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. |
| Electronic Mail; the communications system whereby messages can be sent from one computer to another with the use of networking. | |
| ECDIS | Electronic Chart Display and Information System. |
| Edge matching | The process of ensuring that data along the adjacent edges of map sheets matches, i.e. in terms of both position and attributes. |
| EEZ | Exclusive Economic Zone. |
| EMR | Electromagnetic radiation. |
| EOSAT | Earth Observation Satellite. |
| EPA | Environmental Protection Agency. |
| ERS-1 | The first Earth Resources Satellite, launched by the European Space Agency. |
| ESA | European Space Agency. |
| ESIS | European Seabed Information Service. |
| ESRI | Environmental Systems Research Institute; the software house which produces Arc/Info GIS. |
| False colours | The assigning of arbitrary colours to data values in a remotely sensed image. |
| Feature code | An alphanumeric code which describes and/or classifies geographic features. |
| FFIS | Foreign Fishery Information System. |
| Field | A subdivision of a record which contains one unit of information, e.g. the answer to a single question. |
| File | A collection of related information stored in a computer; often part of a database. |
| Format | The physical organisation of data elements within a dataset. |
| FOV | Field of View: the angle through which a sensing instrument is sensitive to radiation. |
| GEBCO | General Bathymetric Chart of the Oceans. |
| Generalisation | The 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. |
| GENIE | Global Environmental Network for Information Exchange. |
| Geocoding | Allocating a code to represent the spatial characteristics of an entity. |
| Geodesy | The branch of mathematics which is concerned with making accurate measurements of large portions of the Earth's surface. |
| Geomatics | The complete geographical information technologies. |
| Geo-reference | The grid coordinate allocated to a particular location as a means of linking an object with that location. |
| Geostationary | A 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. |
| Geostatistics | A branch of statistics which is concerned with the mathematics of spatial surfaces. |
| GFCM | General Fisheries Council for the Mediterranean. |
| Gigabyte | 1000 megabytes. |
| GIS | Geographic(al) Information Systems; the hardware and software systems necessary for capturing, storing, editing, integrating, manipulating, analysing and displaying spatially referenced data. |
| GISCO | Geographic Information Systems of the European Community. |
| GIST | Geographical Information Systems Tutorial; a GIS training software package. |
| GISTARS | Geographic Information STARter System; a GIS training package. |
| GPS | Global Positioning System; a set of satellites which transmit signals which can be decoded by receivers to determine positions anywhere in the world. |
| Graphical data | Data 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. |
| GRID | Global Resources Information Database (of the United Nations Environment Programme). |
| Ground truth | The 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. |
| GUI | Graphical 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. |
| Hardware | The physical equipment in a computer system. |
| HMMR | High-resolution Multifrequency Microwave Radiometer. |
| HO | Hydrographic Office (in the UK). |
| ICCAT | International Commission for the Conservation of Atlantic Tunas. |
| ICES | International Council for the Exploration of the Seas. |
| ICLARM | International Center for Living Aquatic Resources Management. |
| ICOIN | Inland Waters, Coastal and Ocean Information Network. |
| IDIAS | Ice Data Integration and Analysis System. |
| IFM | Integrated Fisheries Management. |
| IFOV | Instantaneous Field of View; a term used to describe the ground resolution of a remote sensing scanner. |
| Image analysis | The transforming and interpretation of remotely sensed digital data, with the help of special hard- and software systems. |
| Inmarsat | A new series of communication satellites which will be used by global positioning systems to give highly accurate locations on the Earth's surface. |
| Interactive | The operation of a computer system through processing continual, instantaneous communication between the operator and the machine. |
| Internet | An international computer communication system over which information is distributed. |
| IOC | Intergovernmental Oceanographic Commission (of the United Nations Educational, Scientific and Cultural Organization) |
| Isolines | Lines on a map which join places having equal values, e.g. contour lines. |
| Isotropic | Pertaining to surfaces on the Earth which are uniform in all directions. |
| IT | Information Technology. |
| ITQ | Individual Transferable Quota. |
| JANET | Joint Academic Network; a UK computer network linking academic and research sites. |
| Kilobyte | One kb = 1024 bytes. |
| Kriging | A spatial interpolation technique which was originally developed in the mining industry. |
| LAN | Local Area Network; the linking of computing systems, usually within a single department. |
| Landsat | A series of US polar orbiting satellites, first launched in 1972 by NASA, which carry both the multispectral scanner and thematic mapper sensors. |
| Layer | A subset of digital map data which contains information all relating to one subject, e.g. water quality or the coastline. |
| Line | In 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. |
| LIS | Land Information Systems; a GIS for land resources management and an acronym given to some early GIS's. |
| Liveware | The name sometimes given to the personnel who operate computer systems. |
| LME | Large Marine Ecosystem; areas of the sea having unified hydrographic regimes and trophically related marine populations. |
| MARIS | Marine Information Service. |
| MARSIS | Marine Remote Sensing Information System. |
| MCB | Marine Catchment Basin. |
| MEDS | Marine Environmental Data Service. |
| Megabyte | One Mb = 1,048,576 bytes. |
| Meta database | A 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. |
| Microcomputer | A small stand-alone computer processing unit. |
| MODEM | A MOdulator-DEModulator: a digital device which allows computers to communicate with each other via the telephone network. |
| Mosaic | A map or satellite image, compiled from several different images. |
| MSS | MultiSpectral Scanner; a remote sensing device that records electromagnetic energy in several wavelength bands simultaneously. |
| Multimedia | The use of text, data, still and motion video, sound and computer graphics by a software programme to form a composite display. |
| NAFO | North Atlantic Fisheries Organisation. |
| NCGIA | National Center for Geographic Information and Analysis: a US research center for GIS. |
| NCIC | National 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. |
| Networking | The use of a computer plus a MODEM link to obtain access to remotely held databases. |
| Nimbus | A 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. |
| NLR | National Aerospace Laboratory; a Dutch distributor of remote sensing products. |
| NOAA | National Oceanographic and Atmospheric Administration. |
| NODC | National Oceanic Data Center. |
| Node | The start or end of a link or line; a point which can be shared by several lines. |
| NOS | National Ocean Service. |
| NRSC | National Remote Sensing Centre. |
| NTF | National Transfer Format. The UK standard for the transfer of geographic digital data - it has now become a British Standard (BS7567). |
| NWI | National Wetland Inventory. |
| Object | Computer programmes which use object oriented oriented techniques and languages. These employ a programming data centred approach to programming, based on the definition of “objects”. |
| OCM | Ocean Color Monitor. |
| Octree | A representation for compressing data which is geo-referenced in 3- D (using voxels). |
| ODES | Ocean Data Evaluation System. |
| Operating | The 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 disk | A 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. |
| Orthophoto | A photograph which has been manipulated so as to eliminate image displacement due to photographic tilt and relief. |
| OS | Ordnance Survey (Great Britain). |
| Overlay | A set of graphical data which can be superimposed on to another set of graphical data. Sometimes used as a synonym for layer. |
| Package | A generalised programme capable of performing several operations and covering the requirements of many users. |
| Passive sensor | A device which captures and records natural radiation reflectance levels. |
| Peripheral | Any hardware device added to a computer system. |
| Photogrammetry | The technique of obtaining precise measurements from images. |
| Pixel | From Picture Element: the smallest unit whose characteristics may be uniquely determined; an individual dot on the screen. |
| Platform | In remote sensing, the physical object which carries the sensors that make the remote measurements. |
| Plotter | A 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 orbiting | The 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. |
| Polygon | A closed, two dimensional figure with three or more sides and intersections, e.g. a geographic area such as a field or other land unit. |
| Preprocessing | The manipulation of data, via a large number of techniques, to make it suitable for further manipulations or analysis. |
| Primary data | Data which has been directly gathered from real world situations by surveys, questionnaires, measurements, etc. |
| Programmable | Any computing or data recording device which can be pre- programmed to carry out any desired functions. |
| Projection | The systematic construction of features (physical and political) on a plane surface to represent corresponding features on a spherical surface. |
| Protocol | In data communications, a set of rules which determine the formats and conventions by which information may be exchanged between different systems. |
| Push broom | An airborne sensor which functions by taking sensorcomplete frames (pictures) of any scene over which it passes. |
| Quadtree | A spatial data structure based on successive subdivision of an area, the purpose of which is to minimise data redundancy. |
| Radiometer | A passive device for intercepting and quantitatively measuring electromagnetic radiation in a band of wavelengths. |
| RAM | Random Access Memory; a type of chip based memory which a computer processor can read data from and write data to. |
| Raster | A format for storing, processing and displaying graphic data in which graphic images are stored as values for uniform grid cells or pixels. |
| RDBMS | Relational Database Management System: a widely used strategy for data organisation in GIS software. |
| Record | A collection of related fields, e.g. all the responses from one questionnaire. |
| Registration | The superimposition of locations on one image with the corresponding locations on a second image or map. |
| Remote sensing | Obtaining information about an object or phenomenon without any direct contact, e.g. via the use of satellite sensors or Radar. |
| Resolution | The minimum size of a feature which can be reliably distinguished by a remote sensing system. |
| RESTEC | Remote Sensing Technology Center. |
| ROM | Read Only Memory; a type of chip based memory which a computer processor can read data from but cannot write data to. |
| Rubber | A GIS process that geometrically adjusts map sheeting features to enable a digital map to fit a designated base. |
| Run-length | A method of digital coding which saves on the encoding amount of data which needs to be stored. |
| SAR | Synthetic 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. |
| Scanner | A device used to capture data digitally from a paper map or other graphic representation. |
| Seasat | A 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. |
| SeaWIFS | Sea-viewing Wide-Field-of-View Sensor. |
| Secondary data | Data which has been acquired from previously published sources. |
| Sensor | A device that gathers electromagnetic radiation or other physical data and presents it in a form suitable for obtaining information about the environment. |
| Signature | A set of spectral, tonal, temporal or spacial characteristics that together serve to identify a class or feature by remote sensing. |
| Software | A computer programme written in a high or low level language. |
| Spaghetti data | A simple vector data structure comprising feature codes and co- ordinates without any topology. |
| Spatial data | Data or information describing the geographical position or location of an object. |
| Spectral | Typical radiation reflectance values as given signatures off by different ground or water surfaces. |
| Spline | A mathematical formula for drawing regular function curves. |
| SPOT | Satellite pour l'Observation de la Terre. A French multispectral remote sensing satellite system having pointable sensors, which was first launched in 1986. |
| SQL | Structured Query Language; a query language interface for relational databases. It is used to define, access and manipulate data stored in these databases. |
| Standards | In computing, the establishment of a unified set of procedures for handling digital data. |
| Swath width | The area on either side of a platform which is surveyed by a remote sensing instrument. |
| SYMAP | Synagraphic Mapping System; one of the earliest and most widely used computer mapping systems, producing crude line printer output graphics. |
| TAC | Total Allowable Catch. |
| Telnet | Telecommunications Network. |
| Thematic map | A map depicting one or more specific themes, e.g. rainfall or population density. |
| TIN | Triangulated 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. |
| TM | Thematic Mapper; a seven channel multispectral scanner sensing device, designed for monitoring the Earth's surface, and flown on the Landsat series of satellites. |
| Topography | The collective features of the Earth's surface, including relief, hydrology and cultural features. The features may be accurately located on topographic maps. |
| Topology | A geographic data structure in which the inherent spatial connectivity and adjacency relationships of features are explicitly stored and maintained. |
| Transducer | That 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. |
| Transformation | The ability to change from one coordinate system to another. Sometimes also called rectification. |
| Turnkey system | A complete computer system consisting of a hardware and software combination which has been assembled in order to perform a specified range of tasks. |
| UKDMAP | United Kingdom Digital Marine Atlas. |
| UNCLOS | United Nations Convention on the Laws of the Sea. |
| UNEP | United Nations Environmental Program. |
| Unique | An 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. |
| USGS | United States Geological Survey; the organization dealing with US governmental topographic mapping. |
| USNO | United States Naval Observatory. |
| UTM | Universal 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. |
| VDU | Visual Display Unit; commonly thought of as a computer screen. |
| Vector | In 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. |
| Videography | The use of video cameras on airborne platforms to capture images of the Earth. |
| Visualization | The 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. |
| Voxel | A data structure used to assign geo-references in a 3-D spatial model. |
| WADABA | Wadden Sea Data Base. |
| WAN | Wide Area Network; the link up of computing systems over a wide spatial area. |
| WATIS | Wadden Sea Information System. |
| WINS | Weather Information Network System. |
| WOCE | World Oceanic Circulation Experiment. |
| Workstation | A 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. |
| WVS | World Vector Shoreline. |
