The general theme with these shapes is the dominant 7th sound, which is essentially a major chord plus a b7th. This is a ...

In blues ‘dominant’ 7 chords (A7 or D7 for example) are more common than basic major, minor and sus chords. The A7, D7 and E9 ...

You can learn to play the guitar with only a few chords, and there are plenty of free websites to help you along the way.