The clip is shared online as the Metrolink chime, a transit alert most uploaders simply label as a train coming sound. Metrolink is the name used by commuter rail and light rail networks, and chimes like this are played in stations and onboard trains to signal arrivals, departures and closing doors. Short transit sounds travel well on soundboards because they are instantly recognizable, and this one has stuck around as a handy shorthand for anything rail-related, from fan recordings to meme edits about commuting.