Technically, UPC refers to UPC-A. This code comes with 12 numbers, and no letters or characters. A unique UPC-A is assigned to different variants of the same item. UPCs, along with their related International Article Number (EANs), are commonly used to scan items at point of sale terminals according to GS1 standards. The data structure of UPC is a component of Global Trade Item Numbers (GTINs).
Every UPC-A comes with a barcode of black bars printed over white space that may be scanned using a suitable device. The barcode is placed directly above the 12-digit UPC-A. There is a direct relation between the barcode and the numbers. Representing the set of numbers through the barcode is possible in only one way, and the reverse holds true as well.
The UPC-A standard follows a simple format. The first number represents the number system digit. The next set of five to eight numbers identifies the manufacturer number that is assigned by GS1. The next set of numbers represents specific products, with each variant having a unique UPC-A. The last number functions as a check digit.
The number system digit indicates the type of numbering system used by the code in its entirety.
The UPC standard comes with a few other variants, which include:
GS1, an international non-profit organization headquartered in Brussels, is responsible for developing, maintaining, and regulating the UPC standard. The Uniform Code Council controls the UPC-A system and assigns manufacturer numbers in the United States.
The UPC standard was developed by IBM in the early 1970s. The task was mainly assigned to George Laurer and Heard Baumeister.
Here are a few UPC-As to serve as examples:
190198071842 – iPhone 7, 128 GB, Unlocked, Silver
190198155795 – iPhone 7 Plus, 32 GB, Unlocked, Black
190198459107 – iPhone X, 64 GB, Unlocked, Silver