The sound comes from League of Legends, Riot Games' multiplayer online battle arena released in 2009, where it signals that matchmaking has found a game and players must accept within seconds. As League became one of the most played PC games in the world, the cue was heard millions of times daily and became shorthand for being ready to play. Clips of the queue pop spread through streams, montages and soundboards alongside other game notification sounds, and creators now use it outside the game to announce matchups, decisions and starting moments.