Happy chord loop

I-V-vi-IV: a chord loop of 4 bars that comes round again and again.

Chords: C, G, Am, F

Questions

What chords are in the Happy chord loop?

In C it is C, G, Am and F: I-V-vi-IV in roman numerals. In any other key the numerals stay the same and the chords move with them.

How do you play it on piano?

The left hand plays the root of each chord and the right hand holds the chord, one chord a bar. In another key the chords move with it.

Which songs use the Happy loop?

Love Story by Taylor Swift, All Too Well by Taylor Swift and Nuvole Bianche by Ludovico Einaudi use the Happy loop. The songs on this page all go round these chords, the most played first.