The phrase comes from everyday Brazilian Portuguese online speech, where td is shorthand for tudo and vcs is shorthand for vocês, the kind of abbreviation common in WhatsApp messages and social media captions. As a sound, it circulates as a short WhatsApp audio and meme greeting, shared between friends and family groups rather than tied to a film, song or television show. Its appeal is its familiarity: anyone who uses Brazilian group chats recognises the check-in instantly, so creators keep reusing it to signal closeness, humour and a relaxed, informal start.