What is GeoTIFF ?
GeoTIFF format is a non-proprietary geographic TIFF format. The purpose of GeoTIFF is to provide information that lets raster imagery (scanned maps, satellite images, results of geographic analysis, etc) be read automatically into correct position and scale within many GIS softwares. GeoTIFF implements a tag structure which embeds the geographic information methodically and interoperably (and invisibly to most users) inside the TIFF file.