is a manual for undergraduate students in engineering and the natural sciences to discover how computer programming works. Using a dialog format between two students and a professor, the text teaches students how the mainstream web languages HTML, CSS, and JavaScript interact and how to harness their capabilities in practical settings. Each chapter focuses on a specific theme supported by a gradual development of engaging worked examples of live web documents and applications using the three languages. Students can follow most of the examples and experiments using any modern browser and plain text editor. A practical homework problem is included at the end of every chapter and then is discussed at the beginning of the next chapter. In addition, a related keywords list helps students review key topics. By focusing on important established principles and concrete examples, this introductory book shows students how to write cleaner and more easily maintainable code. It augments the basic language syntax and rules with contents and structure while keeping the material simple and manageable.