H1-KEY's song "RUN" is about feeling free and alive. The lyrics describe the feeling of a good morning and the joy of a sunny day. The song encourages listeners to run and be active, promising that they will feel better and happier. The upbeat tempo and positive lyrics make "RUN" a feel-good song that inspires listeners to enjoy life to the fullest. Overall, the song is about living in the moment and finding happiness in small things.