The line comes from Friends, the long-running American sitcom that aired from 1994 to 2004, where Joey Tribbiani used 'How you doin'?' as his signature flirty greeting. It became one of the show's most quoted catchphrases and survived through reruns, DVD box sets and streaming, before finding a second life in memes, reaction videos and short-form edits. Its appeal is simple: the phrase is instantly recognisable even to people who never watched the show, and it instantly signals playful confidence.