The sound comes from Undertale, the 2015 indie role-playing game created by Toby Fox. In the game, most conversations happen in text boxes, and each character has a distinct short vocal blip that repeats as their lines type out, giving silent text a sense of voice and timing. Frisk, the human child protagonist, is mostly silent, so this neutral typing effect became closely linked to the character in fan works. It spread through Undertale fan games, animations, and meme edits, and remains popular for recreating the game's dialogue style.