What is an ISBN?
ISBN is the acronym for International Standard Book Number. This 10 or 13-digit number identifies a specific book, an edition of a book, or a book-like product (such as an audiobook). Since 1970 each published book has a unique ISBN. In 2007, assigned ISBNs changed from 10 digits to 13.
Finding the ISBN number on a book
On most books, the ISBN number can be found on the back cover, next to the barcode. If a book doesn't show the ISBN on the back cover, look on the page featuring the copyright and publisher information and the ISBN will be found there.
ISBN on the back cover
Important note
ISBN numbers were introduced in 1970. Any book printed before 1970 will not have an assigned ISBN.
Why search by ISBN
ISBNs are useful when looking for a specific printing of a book. A student, for example, can search by ISBN to find the correct edition of a textbook for school.
Books will have a different ISBN number for the softcover version than for the hardcover edition. The ISBN will also vary depending on the country of publication. A popular book that has been reprinted numerous times over the years will have many different ISBN numbers - one for each publication. If you are looking for a specific edition, binding or even cover art of a certain title, knowing the ISBN will be extremely helpful when searching for the book.
Examples of some different ISBN numbers associated with Pride and Prejudice by Jane Austen
