electronic ticket is a " paperless " airline ticket allowing one to Check-In and fly with just proper photo ID. What may look like a ticket is actually just a paper passenger receipt.
E-tickets cannot be lost, or used by anyone else, so they are safer than standard paper tickets, which may soon become extinct. One drawback is that e-tickets on one carrier cannot be honored by another, so in a cancelled-flight snafu, the original carrier must print hard copy tickets before another airline can accept them. This presents major paperwork problems for the affected carrier
Other definition:
Electronic Ticket is the Ticketing system in which the passenger receives a confirmation number in lieu of a traditional paper ticket. An ID card is matched with the PNR relating to the confirmation number.
Other definition:
Electronic ticket is a virtual ticket characterized by unique code assigned by the travel company upon itinerary purchase that enables the passenger to complete the journey without obtaining a classic paper ticket from the issuer. It is strongly advised to print out the confirmations with these unique codes and bring them on the trip as a backup.
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