This Australian trio decides they aren’t internationally famous because they’ve never written a four chord song, and then shows us all what one (or dozens) sound like.
This video is an excellent way to see how closely most songs are related (even if they sound unique on their own). This chord progression doesn’t fit every song you’ve ever heard, but you may be surprised how many do fit (you might even think of several examples they didn’t include).
Once you learn those four chords (officially called chords I, IV, V, and vi, which in this song are played in this order: I-V-vi-IV), there’s no stopping you. There’ll be more on chord progressions and how to use them later this month.