ISBN is an acronym used internationally and stands for International Standard Book Number. This is a numerically based unique identifier assigned to every publicly printed book generated through the Standard Book Numbering Code. Some privately-printed books will also contain an ISBN depending on the author or printer’s knowledge of the necessary procedures.
In general, ISBNs are now standardized to have thirteen digits, though this may not be the case for books printed prior to 2007. The ISBN for an item can be found on the packaging and/or back cover of the specific product located above the bar code. In the event that the Seller has an item that is lacking an ISBN, see Adding UPCs, EANs and ISBNs for Your Products for instructions on how to add an appropriate code, or read the page on Locating Product Identifiers for help on finding the ISBN.