With its sweetly cascading hook and romantic lyrics, Vanessa Carlton's early-'00s smash “A Thousand Miles” gave the teen-pop world a dose of piano-borne grandeur. Over the course of her career, Carlton has combined ideas of classical composition and pop songwriting, although exactly how those two come together has shifted over time. She employed string flourishes and big choruses on early tracks such as “Ordinary Day,” brought in rock influences on songs including “Nolita Fairytale,” and presented stripped-down tableaus on later tracks such as the hauntingly nostalgic “Blue Pool.”