The phrase I don't know has been shortened online to IDK for decades in texts and chats, and this audio version turns that shorthand into a spoken reaction. Short voice clips like this spread through meme soundboards and short form video because they are instantly understood without explanation. Creators reuse it as a universal response to trivia fails, homework questions, and situations where any real answer would be less funny. Its popularity comes from its simplicity, anyone can place it over a face and the joke is complete.