
Early influences of Tchaikovsky, Rimsky-Korsakov, and other Russian composers gave way to a thoroughly personal idiom that included a pronounced lyricism, expressive breadth, structural ingenuity, and a tonal palette of rich, distinctive orchestral colors. The piano is featured prominently in Rachmaninov's compositional output. He made a point of using his own skills as a performer to explore fully the expressive possibilities of the instrument. Even in his earliest works he revealed a sure grasp of idiomatic piano writing and a striking gift for melody.
Source: Wikipedia