GDAL

GDAL/OGR is the Rosetta Stone of the free GIS world. It will read and write many many GIS data formats and also comes with a whole bunch of useful command line tools for working with this data.

• Supported raster formats
• Supported vector formats
• Included command line utilities

Homepage:

http://gdal.org

NOTE: All GDAL/OGR user docs also available as one PDF.