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Glossary of Map terms

A glossary of map terminology as used in the British Library.


ABRSAutomated Book Retrieval System - used for ordering material to the Reading Rooms
CatalogueA list of all the maps in a collection
CollectionCan refer to the entire British Library Collection or the private collection of an individual or organisation, that has been purchased or donated to us.
ContourA line of equal height, used to display a 3D surface on a 2D map
Digital mapsMaps stored in a digital format accessible on a computer, rather than paper
EditionRefers to the date at which a map or series was made
Estate mapA map of an estate, often a manuscript and usually at a large scale. Can be useful for studying land prior to OS mapping.
FacsimileAn exact copy of a map or atlas; can be studied in preference to the original to save wear and tear on a fragile or valuable item.
Hydrographic ChartA map used for navigation at sea, with water depths and coast line features marked. Often referred to as Admiralty Charts.
Hydrographic OfficeGovernment agency publishing hydrographic charts
GazetteerA book containing an list of placenames, generally alphabetical, with their locations. Some include a description of the place as well. Can be used to locate a place on a map.
GlobeA map of the world or a celestial map on a sphere, allowing for a more accurate representation of the Earth's surface than can be shown on a flat map.
GoresA globe laid out flat. These are the flat paper section that are used to cover a globe.
GraticuleThe lines of latitude and longitude on a map.
Grid ReferenceA location defined by X and Y coordinates, on a particular grid. The most commonly used grid for the UK is the OS National Grid.
Index mapDiagram showing which sheet in a map series covers which area.
Manuscript mapHand drawn map, as opposed to printed map. Often rarer and more fragile than printed maps.
MBHSMechanical Book Handling System; used to transport collection items from storage areas to the Reading Rooms.
MicroficheA small sheet of acetate with a map or image printed on it, reduced to a fraction of its original size. It requires a microfiche viewer. Reduces use of the original and allows easy printing.
MicrofilmA roll of film with a number of maps or images printed on it, reduced to a fraction of original size. It requires a microfilm viewer. Reduces use of the original and allows easy printing.
MonographA specialist book dealing with one particular subject
Ordnance Survey (OS)The national mapping agency of Great Britain. Ordnance Survey of Northern Ireland (OSNI) and Ordnance Survey of Ireland (OSI) also exist.
Printed mapA map produced by printing, as opposed to a manuscript map.
ProjectionThe method by which the curved surface of the globe is represented on a flat sheet of paper. There are dozens of different projections for different purposes.
ScaleA ratio that indicates the size of the area that a map represents.
Large scale - More detailed, smaller area e.g. 1:2 500
Small scale - Less detailed, larger area e.g. 1: 1 000 000
Some examples of different scales.
Series mappingA set of maps covering a country/region/continent on a large number of sheets. Sheets may be arranged in a grid. An index map is used to find a particular sheet number in a series.
Sheet mapMap on a separate sheet of paper as opposed to in a volume or atlas
Thematic mapMap showing statistical rather than topographical information about a place e.g. map showing population density or land use.
Topographic viewAn accurate drawing (printed or manuscript) of a place. Can provide information not found on a map, such as the style of housing or land use; often useful for historical research.