He was well known for the free concerts he held for prisoners and by starting most of his concerts with the words "Hello, I'm Johnny Cash". Lots of his music focused on making good or bad choices in life and what happens after choices are made. It also focused on sadness and being saved or forgiven by God. Some of his best known songs are "I Walk the Line", "Folsom Prison Blues", "Ring of Fire", "God's Gonna Cut You Down", "A Boy Named Sue", "Hurt", "Mister Garfield", and "Man in Black". Cash often recorded songs that other singers first made popular.