Geographic information systems gather and store geographical data. Some examples are desktop GIS, web servers, spatial database management systems, etc. A number of disciplines benefit from this technology, specially the fields of geography, forestry and topography. Some of the main applications of geographic information systems include national security, landscape architecture, archaeology, etc. This book includes some of the vital pieces of work being conducted across the world on various topics related to geographic information systems. As this field is emerging at a rapid pace, the contents of this book will help the readers understand the modern concepts and applications of the subject.