A First Text on Geographic Information Systems Geographic Information Systems (GIS) are computer-based tools for the entry, maintenance, and analysis of spatial data. GIS are critical for effective resource management, and have been applied across a wide range of science, business, and government endeavours. This book provides an introduction to the theory and application of GIS. It is written for use in a first-year GIS class and as a reference for the GIS practitioner. This sixth edition balances theoretical and practical material, so that students may apply knowledge of GIS in the solution of real-world problems. Improvements over the previous editions are included in each chapter. Topics treated include an introduction to GIS, spatial data models, map projections, data entry, image data, GPS, digital data, database systems in GIS, general spatial analysis, raster analysis, terrain modeling, metadata, standards, and accuracy assessments. The bestselling GIS textbook by Paul Bolstad is now even better!