Sometimes called the MapInfo Native format or the MapInfo TAB format, the MapInfo dataset format is a proprietary format developed for use with MapInfo software products. A MapInfo dataset consists of a number of physical files. Two files are required for textual and numeric data without graphic objects. The table structure in ASCII format ( *.TAB ) is the main file for a MapInfo table. The .TAB ASCII file is the link between all other files and holds information about the type of data file. The attribute data (*.DAT) is stored in binary format. These two files support a ‘browser’ view of the tabular data, a view comparable to a spreadsheet. To display geographic information (the graphic representation of data in vector form) in Mapinfo Professional, using the ‘mapper’ view, two additional files are required. Map objects are stored in binary format and represented in a *.MAP file. Graphic data is linked to database information in a file (*.ID) that contains a 4-byte integer index into the MAP file for each feature. A fifth file, in binary format, (*.IND) is present if any fields are indexed and serves as an index to the MapInfo tabular (*.DAT) file. The format is sometimes described as TAB/MAP. Open source software is available for reading and writing MapInfo datasets in the MapInfo Native (TAB/MAP) format and the MapInfo Interchange Format. Geospatial Data Abstraction Library (GDAL/OGR) is a cross platform C++ translator library for raster (GDAL) and vector (OGR) geospatial data formats that is released under an X/MIT style Open Source license by the Open Source Geospatial Foundation. The MapInfo dataset formats are supported in OGR. The MITAB software library and utilities make use of the OGR software to provide a tool specifically for MapInfo datasets. The USGS Digital Data Viewer: dlgv32 Pro, a limited-feature version of commercial software Global Mapper, originally from the U.S. Geological Survey (USGS), can import and export data to the MapInfo MIF/MID (MapInfo Interchange Format) and TAB/MAP formats. MapInfo Pro implements OGC’s Web Map Service (WMS) and Geography Markup Language (GML) specifications. Pitney Bowes’ Envinsa and MapExtreme products are OGC WMS compliant. The MapInfo Professional User Guide includes a brief description of the component files in a MapInfo table, which is summarized here. All MapInfo Professional tables have the following two files: When using a remote table such as Oracle Locator or Spatial, if the data is downloaded to the local machine, the temporary file extensions are: MITAB is an Open Source C++ library to read and write MapInfo TAB (binary) and MapInfo Interchange (MIF/MID) files. MITAB is based on the OGR library which is an implementation of the Open GIS Consortium Simple Features specifications for OLE/COM and CORBA. Source.