Bag tag

Bag tags, also known as baggage tags, baggage checks or luggage tickets, have traditionally been used by bus, train, and airline carriers to route checked luggage to its final destination. The passenger stub is typically handed to the passenger or attached to the ticket envelope:

a) to aid the passenger in identifying their bag among similar bags at the destination baggage carousel;

b) as proof—still requested at a few airports—that the passenger is not removing someone else's bag from the baggage reclaim hall; and

c) as a means for the passenger and carrier to identify and trace a specific bag that has gone astray and was not delivered at the destination. The carriers' liability is restricted to published tariffs and international agreements.

The first "separable coupon ticket" was patented by John Michael Lyons of Moncton, New Brunswick on June 5, 1882. The ticket showed the issuing station, the destination, and a consecutive number for reference. The lower half of the ticket was given to the passenger, while the upper half, with a hole at the top, was inserted into a brass sleeve and then attached to the baggage by a strap.

At some point, reinforced paper tags were introduced. These are designed not to detach as easily as older tags during transport.

The Warsaw Convention of 1929, specifically Article Four, established the criteria for issuing a baggage check or luggage ticket. This agreement also established limit of liability on checked baggage.

Prior to the 1990s, airline bag tags consisted of a paper tag attached with a string.

The tag contained basic information:

These tags became obsolete because they offered little security and were easy to replicate.

Current bag tags include a bar code using the Interleaved 2 of 5 symbology. These bag tags are printed using a thermal or barcode printer on an adhesive thermal paper stock. This printed strip is then attached to the luggage at check-in, allowing automated sorting of the bags by bar code readers.

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Wikipedia