Rock'n'roll chords
The are no chords named "rock'n'roll chords", but some certain chords are more suitable for the genre and have been used widely in the styles of rock'n'roll and rockabilly.
Double stops
Theoretically not considered as chord, double stops could still be treated in the context of (inverted) 5th chords. Chuck Berry was one of the first to use these and you will mostly
be occupy string pairs belonging to the fourth highest strings, in the treble region so to say.
A5/E
D5/E
E5/B
C5/G
These can be combined with licks and shuffle patterns. One example of shuffle pattern with a A5-A6 combo is XXXX55 and XXXX75.
In a lick context:
3-strings chop chords
Chop chords are chord that have been "chopped", in other words abbreviated - only some of the notes have been left and this are generally played on the tree or four highest (thinnest) strings. Some of these are close related to so-called triple stops and basically the same thing. Triple stops along with double stops are common in the Chicago blues style.
A
A6
A
D9
E9
Notice that the shapes are movable. You could for example play D6 as XXX 11 12 10.
Learn from video
4 strings chop chords
The 4-strings chop chords are often just extended versions of the shapes above.
A7
E
G
Again, the chords are movable. In the E chord that is based on a open D major shape, the root note is on on the second string.
Drum tracks
The backing tracks are for rock'n'roll style music and involves only drums.