Trade · 6 pages · 12 min
A retail barcode encodes a shared item number for a kind of product, not the identity of one particular package.
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A barcode is a printed pattern that stands for a number, and on ordinary retail goods that number identifies the product type. Every identical item of that brand and variety carries the same code, so a scan looks up one shared record. The opening covers the bars stand for an item number, identical goods share one code, and checkout retrieves the product type.
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