FNC1,ApplicationIdentifiersandElementStrings:EveryGS1-128barcodebeginswithaStartCcharacterfollowedbya(FNC1)"FunctionCodeOne"andanApplicationIdentifier(AI)number.TheAIdefinesaspecificpurposeforthedatafieldafterit.ThecombinationofatheAIanditsdatafieldisreferredtoastheelem