The terms described here are intended to support and clarify the documentation that pertains to OCHRE's implementation of GIS features. Esri, a leader in GIS-based software, has an extensive GIS Dictionary which is an excellent reference.

• Feature table An ArcMap Layer that consists of a number of shapes (features) that has an associated attribute table with supporting information about those shapes.
• Geodatabase An ArcMap-style file of type ".geodatabase" that contains in a single file, available offline, the spatial data in a format accessible to OCHRE. This format is considered to be run-time content appropriate for use with software developed using the ArcGIS SDKs (Software Development Kits). See also this summary of the Esri geodatabase formats.
• Georeference The process of assigning spatial information to an image using some chosen coordinate system. This must be done outside of OCHRE using a GIS-tool such as Esri's ArcMap.
• Shapefile A popular vector-based geospatial format developed by Esri that describes graphic features as points, lines, or polygons with associated attributes. For use in OCHRE each shapefile must have a defined Spatial Reference based on some "well-known" geographic or projected coordinate system. A shapefile has the file extension .shp, along with a number of other sidecar files.