The term "universal product code" (UPC) refers to a type of barcode used to identify products in retail environments. There are several synonyms that can be used to refer to this technology, including barcode, UPC code, GTIN (global trade item number), EAN (European article number), and SKU (stock keeping unit). These terms are often used interchangeably, but each may have slight variations in their meaning or usage. For example, SKU may refer specifically to a product or item number, while EAN may be used more frequently in European markets. Regardless of the specific term used, the goal of UPC technology is to provide a consistent, standardized way of identifying products and tracking inventory across different retail channels.