This book is intended as an introduction to the Dewey Decimal Classification, edition 22. It is not a substitute for it, and I assume that you have it, all four volumes of it, by you while reading the book.

I have deliberately included only a short section on WebDewey. This is partly because WebDewey is likely to change more frequently than the printed version, but also because this book is intended to help you use the scheme regardless of the manifestation in which it appears. If you have a subscription to WebDewey and not the printed volumes you may be able to manage with that, but you may then find my references to volumes and page numbers baffling.

All the examples and exercises are real; what is not real is the idea that you can classify something without seeing more than the title. However, there is nothing that I can do about this, and I have therefore tried to choose examples whose titles adequately express their subject-matter. Sometimes when you look at the ‘answers’ you may feel that you have been cheated, but I hope that this will be seldom.

Two people deserve special thanks. My colleague Vanda Broughton has read drafts of the book and made many suggestions. Ross Trotter, chair of the CILIP Dewey Decimal Classification Committee, who knows more about Dewey than anyone in Britain today, has commented extensively on it and as far as possible has saved me from error, as well as suggesting many improvements. What errors remain are due to me alone.

Thanks are also owed to OCLC Online Computer Library Center, for permission to reproduce some specimen pages of DDC 22. Excerpts from the Dewey Decimal Classification are taken from the Dewey Decimal Classification and Relative Index, Edition 22 which is Copyright 2003 OCLC Online Computer Library Center, Inc. DDC, Dewey, Dewey Decimal Classification and WebDewey are registered trademarks of OCLC Online Computer Library Center, Inc.