This kind of one-word reaction clip has no single credited source, but it has become a staple of online meme editing because it is instantly readable without context. Short reaction shouts travel easily between short-form videos, streams and soundboards, where creators reuse them to punctuate disbelief, confusion or a sudden twist. It sits alongside other short exclamations like oh my god and scream reactions, and its brevity makes it easy to drop into a cut for an audience that recognises the feeling at once.