GS1 is a global organization that develops and maintains supply chain standards, including barcode formats. Its system is widely adopted across industries to identify products, logistics units, locations, and more. A key part of this system is the GS1 Application Identifier (AI) — a standardized prefix that specifies the type...

A GS1 barcode is not a barcode with a special font. It is an ordinary symbology carrying a string of concatenated data elements, and every one of them starts with an application identifier (AI): two to four digits that say what the value means. That single design decision is what...