UPC-A
The Universal Product Code Type A encodes twelve numeric digits: a number-system character, a manufacturer prefix, an item reference, and a Mod 10 check digit, arranged in the fixed-width linear pattern that opened retail scanning in 1974. George Laurer's design at IBM fixed the nominal symbol at an X-dimension of 0.264 mm and a bar height of 22.85 mm, proportions retained as the 100 percent magnification reference in GS1 specifications. Quiet zones of eleven modules on the left and seven on the right separate the symbol from surrounding artwork, and the 1:1.5 aspect ratio governs how far the bars may be truncated. UPC-A is a GS1 data carrier and a valid GTIN-12 representation, and EAN-13 scanners read it by treating the leading position as a zero prefix. Its character set holds no letters: only the digits 0 through 9.
The Universal Product Code Type A is the original barcode symbology that launched the retail scanning revolution. Its 12-digit numeric format encodes a manufacturer prefix and item number with a Mod 10 check digit, and remains the primary product identification standard in the United States and Canada.
UPC-A
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