What are the Ode to Joy chords and how can I play them on the piano?

The chords for "Ode to Joy" are typically in the key of D major and include D, G, A, and Em. To play them on the piano, you would play the D major chord (D-F-A), the G major chord (G-B-D), the A major chord (A-C-E), and the E minor chord (E-G-B) in the appropriate places in the song.