Australian Product Number

Global Trade Item Number (GTIN) is an identifier for trade items developed by GS1 (comprising the former EAN International and Uniform Code Council). Such identifiers are used to look up product information in a database (often by inputting the number through a bar code scanner pointed at an actual product) which may belong to a retailer, manufacturer, collector, researcher, or other entity. The uniqueness and universality of the identifier is useful in establishing which product in one database corresponds to which product in another database, especially across organizational boundaries.
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a number allocated systematically to a product to distinguish it by producer, size, style, etc; the number, also translated into bar code form, is used in marketing decision-making, including stock control and inventory level adjustment. See Bar Code.