E-tickets, or electronic tickets, are digital versions of traditional paper tickets used for travel, events, and attractions. They can be purchased online and are typically sent via email or stored in a mobile app. E-tickets simplify the ticketing process, allowing users to avoid long lines and easily access their tickets on smartphones. When attending events or traveling with airlines like Delta or United Airlines, e-tickets often include a unique barcode or QR code. This code can be scanned at entry points, making it quick and efficient to check in or gain access. E-tickets also reduce the risk of losing physical tickets.