In the modern aviation landscape of 2026, the term "airline ticket" refers to the legal contract of carriage between the passenger and the airline, while an e-ticket (electronic ticket) is the digital manifestation of that contract. Historically, a "ticket" was a physical multi-layered paper document that had to be surrendered at check-in. Today, e-tickets have entirely replaced paper versions; they exist as a digital record in the airline's computer system, identified by a unique 13-digit number and a 6-character PNR (Passenger Name Record) code. When you purchase travel, you receive an "e-ticket receipt" via email, which contains your itinerary and payment details. The primary advantage of the e-ticket is security and flexibility: it cannot be "lost" or stolen in the physical sense, and it allows for seamless online check-in and mobile boarding pass generation. While the "ticket" is the invisible record of your purchase, the "boarding pass" is the document (digital or printed) that actually permits you to pass through security and enter the aircraft.