The chord trinity known as I IV V is one of the most beneficial theoretical concepts for any artist. The I IV V is a skeleton secret for numerous tunes in folk, nation, rock, blues, and beyond, revealing the basic similarities of, say, Louie Louie, Ring of Fire, Johnny B. Goode, Helpless, 3 Little Birds, I Still Sanctuary t Found What I m Trying to find, This Land Is Your Land, Man of Constant Sadness, and I Combated the Law. Understanding I IV V progressions can assist you jam together with songs you ve never played prior to or alter a song s secret without utilizing a capo, and it can get you began writing your own tunes, too.