Piano Notes to be played on a Piano. Learn How to Play Piano. Learn how to play on a piano. Want the letter notes for a song and want to play it on the piano or a keyboard, this is the place. How to Play Hallelujah by Leonard Cohen on a Piano. Got letter notes? Got letternotes? Yes - letter notes, keys, piano chords, bass, and lyrics. YouTube and Website Informational Videos and letter notes for any song. Educational site for musicians and music lovers. LetterNote notation lyrics and more.