The ca-ching sound is a classic money cue modeled on the ring and drawer pop of a cash register. Online, it became a widely reused sound effect for memes, short videos and game edits whenever a creator wants to imply cash, profit or expensive taste. Its staying power comes from how instantly understandable it is: one short hit tells the audience that money is involved. It often appears alongside other simple cues like a ding sound effect for score, reward or purchase moments.