When you know how chord progressions work, it's much easier to learn new songs. And when you understand a song's chord structure, you're not just memorizing letter names, in fact, you can play the tune in any key. Learning how songs are put together also develops your musical ear and enhances your appreciation of music in general.
In this lesson, Fred draws from several musical genres - rock, blues, jazz etc - to illustrate many standard types of chord movement and song structures.
Grossman's (Stefan) Guitar Workshop