Book excerpt: A Practical Guide to Dewey Decimal Classification is a hands-on introduction to the world’s most frequently used classification system. The book gives a brief history of the scheme and discusses the theory behind the organization and construction of Dewey class numbers. However, I would like to go further and walk through the process of finding DDC numbers and how to build them using WebDewey, the online resource for accessing DDC. Since DDC is no longer published in print (as of June 2018), it is important that readers understand the basics of using WebDewey. End-of-chapter exercises let readers assess their learning. Chapter coverage is complete: 1. Introduction 2. Dewey Decimal Classification in a Nutshell 3. Basic Principles of Classification (Exercises at the end of the chapter) 4. Searching and Browsing in WebDewey (Exercises at the end of the chapter) 5. Using Notes and the Manual (Exercises at the end of the chapter) 6. Number Building in DDC (Exercises at the end of the chapter) 7. Using Tables within the Schedules (Exercises at the end of the chapter) 8. Advanced Class Number Building Using Table 1 (Exercises at the end of the chapter) 9. Advanced Class Number Building Using Table 2 (Exercises at the end of the chapter) 10. Advanced Class Number Building Using Tables 3-6 (Exercises at the end of the chapter) 11. Conclusion; DDC Resources Appendix: Answers to chapter exercises