12-bar blues progression in G

A progression is a loop of chords that many songs share. Learn the loop once and you can play dozens of songs that use it.

The Roman numerals say which step of the key each chord sits on. I-V-vi-IV in G is G, D, Em and C; in C it's C, G, Am and F. Same sound, new key.

Play each one at a slow tempo until the changes land on beat one, then switch key and hear the same loop higher or lower.