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Codabar is a linear barcode symbology developed in 1972 by Pitney Bowes Corp. (()). It and its variants are also known as Codeabar, Ames Code, NW-7, Monarch, Code 2 of 7, Rationalized Codabar, ANSI/AIM BC3-1995 or USD-4. Although ''Codabar'' has not been registered for US federal trademark status, its hyphenated variant ''Code-a-bar'' is a registered trademark.〔http://uspto.gov〕 It was designed to be accurately read even when printed on dot-matrix printers for multi-part forms such as FedEx airbills and blood bank forms, where variants are still in use as of 2007. Although newer symbologies hold more information in a smaller space, Codabar has a large installed base in libraries. It is even possible to print Codabar codes using typewriter-like impact printers, which allows the creation of a large number of codes with consecutive numbers without having to use computer equipment. After each printed code, the printer's stamp is mechanically turned to the next number, as for example in mechanical mile counters. ==Check digit== Because Codabar is self-checking, most standards do not define a check digit.〔http://mdn.morovia.com/manuals/bax3/shared.bartech.php#Symbology.Codabar〕 Some standards that use Codabar will define a check digit, but the algorithm is not universal. For purely numerical data, such as the library barcode pictured above, the Luhn algorithm is popular.〔http://www.makebarcode.com/specs/codabar.html〕 When all 16 symbols are possible, a simple modulo-16 checksum is used.〔http://www.barcodesymbols.com/codabar.htm〕 The values 10 through 19 are assigned to the symbols –$:/+.ABCD, respectively.抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Codabar」の詳細全文を読む スポンサード リンク
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