I learnt a lot from reading this book. It begins with a simple introduction of the basic but necessary mathematical tools required to understand how GIS software tools and concepts operate. This understanding opens up new opportunities for users to code new functions into the API's that are becoming standard fare of many of the commercial spatial software.However, the intensity of the contents climb steeply in the middle chapters and the unfocused reader can easily be lost amongst the concepts. Making it to the end of the book will bring a new realization about how our GIS really operates. One good feature is that the chapters are very short and concise, so by the time you are bored, the chapter comes to an end and you can reflect back in sensemaking mode. This is a very understandable book to those who take the patience to read it.