[map projections]
The coordinate system used for displaying geographic data. Examples include the data frame in ArcMap and the view in ArcView GIS.
[map projections]
A pseudo Plate Carree projection used by ArcGIS and ArcView GIS to display data that is in a geographic coordinate system. The angular values of the geographic coordinate system are directly mapped to the display, just as values from a projected coordinate system are mapped. Prior to ArcGIS version 9.2, for data with no defined coordinate system that has values consistent with latitude and longitude values, ArcMap assumed the GCS_Assumed_Geographic_1 geographic coordinate system, which uses a Clarke 1866 spheroid.