*GTIN (Global Item Trade Number) and UPC (Universal Product Code) have an identical meaning, i.e., they uniquely identify a product in a worldwide standardized process.
**Note: GS1 US GTIN is not available to identify medical devices, pharmaceutical products, variable measure products or mixed cases, or to create coupons. This note is copied from the GS1US website.
*** Amazon, Google and other merchants will not accept these numbers as the company prefix is not registered to the vendor in the GS1 Company Database. A partial list of these vendors is barcodestalk.com, nationwidebarcoes.com, singleupc.com, internationalbarcodes.com. Retailers or ecommerce companies who will not accept these numbers in include Amazon, Google, Total Wine etc. More are adding to this list regularly.
**** NDC is National Drug Code. NHRI is National Health Related Industry.