Age of Empires II, first released in 1999, gave multiplayer players a set of numbered chat taunts so they could send quick spoken requests without typing. Number six was the request for stone, a resource needed for walls, towers and castles, making it a familiar sound in team games. As matches moved onto YouTube and streaming, the polite request became a recognisable in-joke among strategy players, and it is now reused in edits and memes whenever someone is short of a vital resource.