World of Warcraft is Blizzard Entertainment's long-running online role-playing game, first released in 2004, and its achievement system, introduced in 2008, gave players goals and rewards beyond levelling and loot. The short chime became instantly familiar to millions of players as the signal that a goal had been completed. As gameplay clips, streams and memes spread on YouTube and Twitch, creators began reusing the sound outside the game as a universal cue for success. It remains popular because it is short, positive and immediately understood, even by viewers who have never played Warcraft.