This book provides a comprehensive introduction about recent state-of-the-art advancements in Open GIS, including Open GIS data, services, software, and libraries for GIS programming. Though GIS software has entered the era of Open GIS alongside the emerging trend of open source software, there is no suitable book for GIS educators to teach our next generation, and for professionals to gain an in-depth understanding about Open GIS technologies and toolkits. This book intends to provide this missing guidance for students, educators and professionals in geospatial fields to quickly find, learn and use a wide arrange of open-sourced data, tools, and programming for geospatial applications. The book begins with an introduction to open data, and discusses data management solutions, including both open-sourced relational databases and NoSQL database systems for big data. Next, the book covers different GIS and remote sensing software, tools and programminglibraries to perform spatial statistics and analyses. Readers will learn about the tools and libraries for desktop and web GIS development for both two dimensional (2D) and three dimensional (3D) mapping and visualization. Finally, the book provides two example of Open GIS applications including public health and natural hazards. At the end of each chapter, practical hands-on exercises are included for readers to fully master the most popular Open GIS technologies introduced in the chapter.