Web and XML Glossary

The ISBN is a nine- or ten-digit number which identifies a specific book title and is recognized worldwide. Publishers assign ISBNs to books to simplify and expedite their ordering and purchase. An ISBN number can often be found on the back of the title page of a book or at the bottom of the back cover, though many older books do not have ISBNs. Sometimes more than one book has the same ISBN, as is frequently the case with books in a series. Book records for books in a series may also contain an ISSN for the series. Separate ISBNs are usually assigned for each format of a book (such as hard-cover or paperback). Newer books frequently also have an EAN-encoded version of the ISBN on their cover.