An electronic ticket, or e-ticket, is an electronic document, an agreement of air transportation between the passenger and the airline company. In fact, it is an electronic version of conventional paper ticket.
Therefore, the passenger may have only his/her ID (passport) to check in and board. The electronic ticket is already stored in the airline's database.
However, we recommend that the passenger have a printed electronic ticket passenger itinerary receipt (ITR) with the booking reference number, which will be sent to your email after payment for the flight ticket. The itinerary receipt (ITR) confirms that you bought the e-ticket. It can be required during check-in, passport and customs control; it will also help you not to forget the time of departure, arrival, or transfer.