Windows 7, released by Microsoft in 2009, came with a set of short system sounds for starting up, logging off and shutting down, and this brief closing melody was the one heard at power-off. As Windows 7 became one of the most widely used versions of Windows, the sound became instantly familiar to millions of users. Years after support ended, creators still reuse it online because it needs no explanation: it signals that something is finished, switched off or over, and that instant recognition makes it a useful shorthand in short videos and memes.