In the video below, you'll find a "backing track." The performer plays a basic 12-bar blues in G major. Anyone who wants to solo over the chords can do so in the privacy of their home, or wherever!

The chords are shown on the screen. If you follow the beat, you should hear three groups of four chords:

1) G7|G7|G7|G7

2) C7|C7|G7|G7

3) D7|C7|G7|D7

The last bar is meant as a "turn around" that links to the first. 

Many rock artists have used the 12-bar blues. Find of a video of one song that is a twelve bar blues, and link and describe it. Does the performer do anything else beside the 12 bars, or are there many repetitions?