Tony the Tiger has been the mascot for Kellogg's Frosted Flakes since 1952, and his catchphrase They're gr-r-reat became one of the most recognised lines in advertising. Originally voiced for decades by Thurl Ravenscroft, the slogan was repeated across television commercials, packaging and jingles until it entered everyday speech as shorthand for enthusiastic approval. Online, the isolated line lives on as a reaction sound because it is short, unmistakable and positive without needing context, making it easy to reuse for memes, edits and celebratory moments.