This product is a globally seamless adaptation of the U.S. Government's Digital Chart of the World (Vector Smart Map Level 0 [VMap0], Edition 5) produced by Global Mapping International in ESRI shapefile format, with added country polygons and updated first-level subdivisions of countries. The underlying Digital Chart of the World was developed by the National Imagery and Mapping Agency (now the National Geospatial-Intelligence Agency)of the U.S. government. GMI has merged the DCW into seamless, global shapefile layers (the original consists of four separate libraries, each divided into dozens of tiles).GMI has also provided sample map project and layer files applying appropriate cartographic symbology to the complex classification system of VMap0). The VMap0 data was compiled from the Operational Navigational Chart (ONC) series of air navigation maps with a scale of 1:1,000,000.Full information about VMAP Level 0, edition 5 is contained in MIL-PRF-89039 PERFORMANCE SPECIFICATION - VECTOR SMART MAP (VMap) Level 0 as amended (VMAP0_spec.pdf)GMI has also provided sample map project and layer files applying appropriate cartographic symbology to the complex classification system of VMap 0 when using the shapefiles in ArcGIS version 8.3 and above.