ISBN (International Standard Book Number) is a unique 10- or 13-digit identifier that is assigned to books and other printed materials to identify and distinguish them from one another. The ISBN is used by booksellers, libraries, and other organizations to identify and track books and other published materials.
The ISBN is issued by the International ISBN Agency, which is responsible for assigning and managing ISBNs. Each ISBN is unique to a specific book or publication, and it is used to identify and locate that specific book or publication. The ISBN is typically included on the copyright page of a book, and it is also used in bibliographic databases to help identify and locate specific books and other published materials.
ISBNs are useful for librarians, booksellers, and other professionals who need to keep track of and access published materials. They help to ensure that these materials can be accurately and consistently identified and tracked over time.