Geographic information systems (GIS) are often comprised of points, lines, and polygons. These data types are called vector data. There is, however, another data type in GIS—rasters. In this chapter, you will learn the basics of working with raster data. You will learn how to:

• Use the Geospatial Data Abstraction Library (GDAL) to load and query rasters
• Use GDAL to modify and save rasters
• Use GDAL to create rasters
• Load rasters into PostgreSQL
• Perform queries on rasters using PostgreSQL