The full English name of ISBN is ISBN. The ISBN consists of ten digits. Divided into four segments by three short horizontal lines, each segment has a different meaning. The first number field is the area code, also known as the group identifier. The shortest number is one digit, and the longest number is five digits, generally taking into account the language, country and region. The countries and regions that voluntarily apply to participate in ISBN system are divided into several regions, and each region has a fixed code: 0, 1 for English. The countries that use these two codes are Australia, Canada, Ireland, New Zealand, Puerto Rico, South Africa, Britain, the United States, Zimbabwe and so on. Stands for French, which is used in French-speaking areas of France, Luxembourg, Belgium, Canada and Switzerland; 3 stands for German and is used in Germany, Austria and German-speaking Switzerland; 4 is the code of Japanese publications; 5 is the code for Russian publications; 7 is the code used in China publications. The second segment number is the publisher identifier, which is assigned by the ISBN center of the country or region. The allowable value range is 2-5 digits. The bigger the publishing house, the more books it publishes, and the smaller the number. The third paragraph is that the book number (title identifier) is given by the publishers themselves, and the book number of each publisher is fixed. The shortest one and the longest six. The bigger the publishing house, the more books published and the longer the serial number. The tenth digit is the parity bit of the electronic computer. Fix one digit, the starting and ending digits are 0- 10, 10 is replaced by X, and four digits should be connected by a hyphen (-) (for example: 2-02-033598-0). However, some library integration systems can't automatically assign hyphens, and library catalogers don't know much about the segmentation of ISBN, so people often omit hyphens in bibliographic records (for example, 2020335980). The calibration method of standard ISBN is weighting method, that is, 9 digits from 10 to 2 are respectively multiplied by the first 9 digits of standard ISBN, and the sum of the product plus the check code is divided by the constant 1 1. If it is separable, the number of instructions is correct; If not, ISBN is wrong. ISBN is used for printed matter, microfilm, educational television or movies, mixed media publications, microcomputer software, atlases and maps, Braille publications and electronic publications. Before 65438+2007 1 October1,the 10 ISBN that has not been allocated by ISBN institutions in various countries can be prefixed with 978. Once the existing 10 ISBN is used up, all newly applied ISBN will start from 979. That is, the 979 prefix is currently used in two situations. First, newly-built publishing houses applied for ISBN for the first time, and existing publishing houses applied for ISBN number after 1 in 2007. Second, if the digits prefixed with 978 are used up first, then you can only use 979.