Types of Application Identifiers (AIs)
There are more than 100 Application Identifiers (AIs), which your business can use to identify additional data within a barcode or RFID tag, just like a phone number’s area code can be added to identify which state you’re calling from and to.
GS1 AIs give your business the ability to carry extra information in a barcode or RFID tag.

Access the Application Identifier Look-up Tool
Identify all kinds of data
GS1 AIs are used to identify all kinds of data. This data can then be captured in a barcode or RFID tag.
AIs are used to represent GS1 ID Keys (e.g. GTIN, GLN, SSCC); and to identify other information, known as attribute data, like variable count, net weight, batch/lot number and expiry date, just to name a few.
Other AIs are used for things like shipment identification, coupons, refund receipts and more.
See the complete list of AIs (go to section 3 in the document)