| Summary: The numbers and their placements tell a lot about the books they represent. When an ISBN is assigned to a book it gives that book an internationally recognized identity. |
ISBN International Standard Book Number, Book Bar Code
Adopted between 1968 and 1972, the International Standard Book Number (ISBN) is a ten digit number assigned to each commercially published book, educational kit, pamphlet, microform, CD-ROM, and Braille publication in the world. When an ISBN is assigned to a book it gives that book an internationally recognized identity that ensures publishers, libraries, and book retailers are able to do business with the confidence that everyone involved is not just talking about a certain title by a certain author, but also the same publisher, edition, and binding. Also, by using numbers instead of titles, ordering and inventorying foreign titles is accomplished with ease and security, knowing that what you want is what you’ll get.
While the presentation of an ISBN can vary from publication to publication, ISBNs themselves are not randomly assigned. The numbers and their placements tell a lot about the books they represent. For example, the first digits indicates the group or country the book is published in – a “0” or “1” is English, “2” is French (Belgium or France), “3” is German (Germany or Austria). The second set of numbers – usually between two and five digits – belongs to the publisher and the third set is the book number itself. The variation of field size depends on the size of the publisher. For example, a large international publisher like Knopf or Simon & Schuster will have a small publisher number so as to leave plenty of room for the quantity of books published by them each year. A smaller publishing house won’t put out as many new volumes each year and will therefore have a longer publisher number. When a publisher runs out of numbers for new titles a new publisher number is assigned.
One interesting feature of ISBNs is that while each book is assigned a ten digit number, only the first nine digits actually represent the book. The tenth digit is a “check sum,” a number used to make sure that the other nine digits are entered correctly. A check sum, or “check redundancy” is calculated by multiplying each of the first nine digits by its place, adding them together, and dividing by 11. If the remaining number is not divisible by 11 then an error occurred in the entry of the ISBN. The final check digit is represented by 0 through 9 or an “x” if the remaining number is 10.
ISBNs are managed internationally by the International ISBN Agency (located within the State Library Berlin, Germany). In the US ISBNs are assigned by R.R. Bowker, a supplier of bibliographic information such as Books In Print and Ulrich’s Periodical Directory.
