The phrase is Turkish for asking what is in the sky, and the humour comes from saying an everyday question in an exaggerated, drawn-out shout. Online, short reaction sounds like this spread because they can be dropped into almost any video without explaining the joke, and this two-second clip is short enough to work as a punchline on its own. Creators use it for sky gags, surprise reveals and moments when a character notices something overhead, and its appeal has lasted because the question is simple, visual and instantly understood even by viewers who do not speak Turkish.