Korail is the operating name for Korea Railroad Corporation, which runs intercity and regional trains across South Korea, and its door sound is part of the everyday onboard experience for passengers. The short chime warns riders that the doors are about to close, before the doors themselves slide shut. Outside Korea, the sound has become familiar through travel videos, train spotting clips and transit edits shared online, where it is used to signal a Korean train setting without needing any explanation. Its clear, functional tone is why creators keep returning to it for realistic rail scenes.