November 28, 2021
The ISBN code (from the English International Standard Book Number, "international reference number of the book") is a numerical sequence of 13 digits used internationally for the classification of books (the encoding prior to 2007 is still used, consisting of a number of digits equal to 10, where the last digit may possibly contain the capital letter X). It is defined by an ISO standard, derived from the English SBN encoding of 1967. Although not mandatory, its use has now become essential for the introduction of the book product in the channels of large-scale distribution. Each ISBN code uniquely identifies each specific edition of a book (but not the simple reprints, which keep the same code as the edition to which they refer) and, once assigned, it can no longer be reused.
There are also analogous numerical codes for the classification of periodical publications such as newspapers or magazines (the ISSN) and for musical scores (the ISMN).
In 1965 Smith's, the largest English chain of large-scale distribution specializing in books and newspapers, announced that it wanted to switch to computerized management of its warehouses and warehouses within a couple of years and, in order to create an adequate cataloging system, commissioned the study to Professor Gordon Foster. In fact, the 9-digit Standard Book Numbering (SBN) encoding was developed in 1966 in agreement with other book sellers and implemented in 1967.
The ISO (International Organization for Standardization) then convened a commission to discuss the possibility of extending this method to international use, a possibility already contemplated and hoped for in Foster's study (including the passage from 9 to 10 digits). The first meeting was held in London in 1968 with representatives from Denmark, France, Germany, Ireland, the Netherlands, Norway, the United Kingdom, the USA and an observer from UNESCO. Other countries contributed with written suggestions and declarations of interest. A report of the meeting was distributed to all ISO members and the various observations were discussed at subsequent meetings in Berlin and Stockholm in 1969, until the 10-digit ISBN was approved as standard in 1970 with ISO 2108. Since 1 January 2007, 3 digits (978 or 979) have been added in front of the "old" ISBN, thus bringing the digits that make up the ISBN from 10 to 13; the algorithm that generates the control character has changed, so the last digit does not generally coincide in the two versions.
The code is normally represented by the OCR-B font.
The current ISBN code consists of a 13-digit string, divided into 5 sectors. Generally, but not always, the various sectors of the ISBN are separated from each other by a hyphen (this is the recommended method) or by a space.
EAN prefix - are the first three digits of the ISBN code, introduced starting from 2007; indicate that you are in the presence of a book.
Language group - is the identifier of the publisher's country or linguistic area; can use 1 to 5 digits.
Publisher - is the identifier of the publishing house or publishing brand; can use 2 to 7 digits.
Title - is the identifier of the book; can use 1 to 6 digits.
Control character - it is the last digit of the ISBN code (in the "old" ISBN-10 codes, in addition to the numbers from 0 to 9, the Roman 10, that is the "X", was also used) and is used to verify that the code has not been misread or transcribed (which can always happen, especially when using automated tools such as barcode scanners). Only the first and last sectors have a fixed number of digits (3 and 1 respectively), while for the other three central sectors the number of digits varies in a complementary way. The three central sectors, taken as a whole, therefore have the remaining nine figures at their disposal; that is