International Standard Book Numbers (ISBN)

A Brief History

The International Standard Book Number has its origins in the Standard Book Numbering system developed in England for bookseller W. H. Smith. The Standard Book Numbering system was introduced in the UK in 1967.

The International Standards Organization, (ISO), investigated the feasibility of adapting the British system for international use in 1968. The International Standard Book Number (ISBN) was approved as an ISO standard in 1970.

ISBN Format

An ISBN has 10 digits, separated by hyphens. In Readerware you can enter ISBN's with or without hyphens, Readerware will automatically add the hyphens in the correct places. The ISBN is divided into 4 parts:

Group identifier (1 digit, typically 0 or 1 for English-speaking countries)
Publisher identifier
Title identifier
Check digit

The check digit is used to validate the preceding 9 digits. The check digit will sometimes be an X. All other characters must be numeric.

ISBN Problems

The publisher identifiers are assigned by various Government agencies. The title identifiers are assigned by the publishers themselves. Therein lies a problem. The ISBN should be unique but a publisher could reuse ISBN's from out of print titles, or simply make a mistake and assign duplicate numbers to different titles. So occasionally you will run across different titles with the same ISBN.

The check digit is calculated from the preceding 9 digits. Unfortunately not all check digits have been calculated correctly. You will sometimes run across a book with an ISBN that has an invalid check digit. This problem occurs mostly on older titles.

Readerware handles this by displaying an error dialog whenever it detects an invalid ISBN. Normally you will get this dialog when you enter an invalid ISBN, so the proper response is to click on Reject and correct the ISBN. However because you will occasionally run across an invalid ISBN on a book, Readerware allows you to override the error and accept the ISBN anyway. You should only override the ISBN error in those rare cases when a book has an invalid ISBN.

Where to find the ISBN

All modern books, (hardcover and paperbacks), include the ISBN on the copyright page. Hardcover books today will include the ISBN as part of the European Article Number, (EAN), commonly referred to as the UPC or bar code, which is located on the back of the book jacket. Paperback books may also include an EAN but mass market paperbacks typically do not. So the bar code on a mass market paperback will not include the ISBN, but a mass market paperback may include the EAN on the inside front cover.

On older books, the ISBN can be virtually anywhere. If the copyright page does not include the ISBN, check the book jacket, typically the spine or the back cover. Books published before 1970 will of course not have an ISBN.

ISBN and bar codes

Remember that anywhere you can enter an ISBN in Readerware, you can enter it via a bar code reader. A bar code reader can make entering and maintaining data in Readerware a lot easier. They are the fastest way to search for a book. See The Readerware Web Site for recommendations on specific bar code readers.

Library of Congress Card Catalog Number (LCCN)

The Library of Congress Card Catalog Number predates the ISBN and can also be useful when cataloging books with Readerware. You will often find the LCCN on books from the fifties and sixties. Sometimes you will find both the ISBN and the LCCN, in that case use the ISBN as it is supported by all the search sites. If a book only has an LCCN, you can search for it at The Library of Congress [2] site.

You will find the LCCN inside the book on the copyright page. It is normally referred to as The Library of Congress Card Catalog Number or LCCN. Sometimes it is there but not identified. The LCCN is normally formatted with a 2 digit year, a hyphen and then the book number. For example 63-10153.

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