SPRING is a freeware GIS and remote sensing image processing system with an object-oriented data model which provides for the integration of raster and vector data representations in a single environment. It has Windows and Linux versions and provides a comprehensive set of functions, including tools for Satellite Image Processing, Digital Terrain Modeling, Spatial Analysis, Geostatistics, Spatial Statistics, Spatial Databases and Map Management.
SPRING is a product of Brazilian National Institute for Space Research (INPE), who is developing SPRING since 1992, and has required over 200 man-years of development and
includes extensive documentation, tutorials and examples. More than 70,000 users from 60 countries have downloaded the software, as of January 2007.