GIS Spatial Data

Spatial Databases 

• Spatial Data refers to information related to a location anywhere on the earth's surface, and allows users to look at an area or geographic feature in relation to other areas (in relation to changes over time and in relation to various factors)
• Spatial Data describes both the location of a geographic feature and its attributes (non-locational information about a feature, usually stored as coordinates and topology.  A feature's attributes may be viewed as descriptive information that is used to classify and/or describe a particular feature.
• Spatial Data exists in many forms including digital maps, paper maps, area photograph prints and digital satellite images; and can be manipulated in desktop mapping or GIS programs such as ArcView, ArcInfo, MapInfo, or Intergraph.  The data can be vector, raster or tabular:
  • Vector Data represents geographic features (entities) as x, y coordinates.  Features are described as points, lines and polygons.  Examples of common vector formats are Arc/Info Export (E00 files), MapInfo MID/MIF files,  DXF and Shape.
  • Raster data is a cell or pixel based method of representing the Earth's features, with each cell or pixel having a value.  Satellite images are raster data as are maps or images created via scanning.  Examples of raster formats are TIFF, GIF, JPEG, and BMP.

 For more information on GIS software and Spacial Data collections and services, please contact Walter Piovesan walter@sfu.ca.