The software stores 2-D grids as COARDS-compliant netCDF files and comes with a comprehensive collection of free GIS data, such as coast lines, rivers, political borders and coordinates of other geographic objects.

More or less comprehensive graphic user interfaces are available from third parties, as well as web applications, bringing the system's functionality online.

Paul Wessel and Walter H. F. Smith created GMT in the 1980s at Lamont–Doherty Earth Observatory, officially releasing it on October 7, 1991 under the GNU General Public License.

The letters GMT originally stood for Gravity, Magnetism and Topography, the three basic types of geophysical data.

[3] Besides its strong support for the visualization of geographic data sets, the software includes tools for processing and manipulating multi-dimensional datasets.