This book is a great primer for a beginner like myself just entering and exploring the world of data visualization, though I can easily see how it can be a great guide for practitioners and experts as well due to the clear methodology and sound reasoning. It has given me a proven framework to plan, consider, design, implement and evaluate data visualizations. I especially appreciate chapter 2 (Setting the Purpose and Identifying Key Factors) and chapter 5's taxonomy of the various data visualization devices and methods. Thank you Mr. Andy Kirk for sharing your knowledge.