UPC-Awas established in 1973 by the Uniform Code Council, Inc. was the first barcode created by. UPC-ABarcodes are fixed-length, high-density, uninterrupted codes. Used for tracking traded items in stores and marking other items. Used primarily in trade to label goods sold through retail.

Each barcode symbol consists of 2 bars and 2 spaces and is 1 to 4 modules wide. Additionally, the barcode contains three sets of elongated strokes for the left and right barcode boundary marks and a central delimiter mark. Two combinations of codes are used to self-check barcodes when encoding characters. The left side of the barcode (6 characters) is encoded in the first combination of odd dark unit strokes (odd parity). The right side is coded by the second combination of codes with an even number of dark units in the stroke (even parity). A check digit is automatically calculated regardless of the input data.

The barcode contains the following data:

 1 digit - system number.

 5 digits - manufacturer code.

 5 digits - product code.

 1 digit - check digit.

As such, the barcode does not contain any information about the characteristics of the product, but only a unique number related to an entry in an international database where all information about a particular product is stored.UPC-AFormat barcode example:

UPC-barcode