This book provides a comprehensive coverage of the techniques, applications, and technologies of remote sensing, as well as the Geographical Information System (GIS). It is organized into three parts: the first part focuses on the basic concepts of remote sensing, digital image processing, and GIS; second part deals with the application aspects in the field of natural resource management; and the third part covers applied aspects of environment and regional planning based on primary field observations. These techniques have been widely used over last two decades, by earth scientists, geologists, geographers, regional planners, environmentalists, archaeologists, topographers, urban planners, and more.