MapInfo Tab

MapInfo Tab is a proprietary, primarily vector data format developed by Pitney Bowes Software (formerly MapInfo Corporation) for use predominantly in its MapInfo Geographic Information System (GIS) product suite. This spatial data format can incorporate information about the geometry and attributes of both point, line and polygon features, making it suitable for a wide range of GIS applications.

Fundamentally, MapInfo tab files are binary files, but are generally accompanied by several other files that together constitute a dataset. These additional files may include index files (.ind and .id), map object data file (.map), and a text-format tab file (.tab), among others. The MapInfo Tab files generally come as a set which usually includes .TAB, .DAT, .ID, .MAP, .IND files. The .TAB file is a small text file containing a reference to the associated .MAP file, along with information about the projection, units and bounds.

The .DAT file is a dBase III format file which provides attribute data for the geometries in the .MAP file while the .MAP file contains the primary data structure for storing the geographic shapes and positions as vector coordinates. The .ID and .IND files are indexing files used to enhance performance when loading and searching for map data.

MapInfo Tab format supports a range of geometric types, including points, polylines, polygons, and text annotations. Additionally, it has support for multi-part features, enabling more complex geometries to be represented. It can also support a robust set of attribute data, each associated with individual geometrical features in a similar way to other vector data formats.

The MapInfo Tab format is optimized for use within the MapInfo software environment, ensuring efficient loading and rendering of spatial information. Interoperability with other GIS software can occasionally be problematic, although most modern GIS software systems provide some level of support to read, and in some cases, write MapInfo Tab files.

An important aspect of the MapInfo Tab format is its support for spatial indexing. This indexing significantly enhances the performance of spatial queries and other geoprocessing operations, especially for large datasets.

MapInfo Tab format also supports multiple coordinate systems and projections, making it possible to store geographic data in a coordinate system appropriate for the region and application in focus.

While the MapInfo Tab format is highly functional within the MapInfo software suite, users should be mindful of its proprietary nature when considering data sharing and interoperability with other GIS software. It is advisable to consider open standards such as the Geography Markup Language (GML) or shapefiles when sharing spatial data with users who may not have access to MapInfo software.