This book is an introductory level GIS book. Its feature lies in that not only main basic knowledge in traditional GIS are included, like mathematical basis, geographic data model, vector and raster data analysis,spatial statistics, and network analysis, as a typical GIS application is also included as a separate chapter, but also GIS customization using Python, GIS integration with remote sensing, and Web GIS, especially Cloud GIS, are included.This book is written for undergraduate students in GIS related major, and graduate students who have some geo-spatial knowledge or skills but want to do related research, and it is also suitable for those who desire to obtain a rich beginning understanding of how GIS is used, and for those people who have already had certain skills in other fields.