This book presents software visualization at a level suitable for a senior level undergraduate or graduate course, or for the interested technical professional. The approach is to give a survey of the field, and then present a specific research framework designed to reduce the effort required to write visualization tools. A wide range of simple program control flow and data structure visualizations are then presented as examples of how to obtain information about program behavior, and how to present it graphically. Source code fragments and screen images illustrate each example.