The Dewey Decimal Classification (DDC) is a pioneering system of library classification, first conceived by Melvil Dewey in May 1873 when he was just 21. The mother of all modern bibliographical classifications, it is still the most widely used library classification in the world. Its use spread rapidly across the United States, then globally, after its initial publication in 1876 – as if the library world had been waiting for it. Today, about 200,000 libraries and information centers of all types in about 140 countries and more than 60 national bibliographies and other catalogs use it to organize their bibliographic resources. Its use in organizing information resources both in traditional media and non-book materials continues unabated. The DDC not only brought a revolution in facilitating the systematic arrangement of knowledge as contained in books, but also proved to be a catalyst in modernizing library management and services.

This handbook covers all aspects of this reigning classification system. For theoretical background, it describes in brief the system's eventful history of almost 150 years. The mechanics of the system, how it has constantly evolved, how it is now governed and maintained and the layout of the print version and the process of subject analysis of documents in the context of the system are explained in detail.

The overriding aim of our work is to explain the operation and application of the DDC, to give a manual to its use. We explain both its print (including print-on-demand) and electronic formats – the looks differ, but the art and science of subject analysis remain the same. This intellectual process is explained in a useful level of detail, especially in Chapter 5, with special attention to practices specific to the DDC.

Because the DDC is primarily an enumerative classification, the major emphasis is on number location through the ladder of systematic schedules (volumes 2–3 in print). With the growing provisions for number synthesis in the system, this book lays more stress on number building using the schedules and six additional tables. A chapter has been devoted to each of these aspects, including one on multiple synthesis, the multi-step number-building process requiring deep subject analysis. All of the examples have been verified and no background knowledge has been assumed on the part of the user.