ISBNkód

ISBNkód, or International Standard Book Number, is a unique commercial book identifier. It is a 10 or 13-digit numeric code. The ISBN is intended to be a unique identifier for books, distinguishing one title and edition from all others. For example, a paperback version of a book will have a different ISBN than a hardcover version of the same book.

The ISBN system was developed in the United Kingdom by David Whitaker in 1965 and was later adopted as an international standard in 1970. The 10-digit ISBN system was first published as an international standard in 1970 as ISO 2108. The 13-digit ISBN standard was published in 2007.

Each ISBN consists of five parts, if possible: prefix element, registration group element, registrant element, publication element, and check digit. The prefix element is either 0 or 1, indicating that the ISBN is an ISBN-10 or ISBN-13. The registration group element identifies the country or language area of the publisher. The registrant element identifies the publisher. The publication element identifies the specific edition and format of the publication. The check digit is a single digit used to validate the ISBN.

ISBNs are assigned by ISBN agencies in each country. In the United States, the ISBN agency is the R.R. Bowker Company. In the United Kingdom, the ISBN agency is Nielsen Book Data.

ISBNs are used by booksellers, libraries, and publishers to identify and track books. They are also used to order books from publishers and to search for books in catalogs. The ISBN system has been a great success and has made it much easier for people to find and purchase the books they want.

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