Things I have learned about playing music that other people might be interested in.
The CAGED system for guitar is an established way to help players to unlock the fretboard. This looks at one possible way of creating a similar framework for open D.
Understanding triads is a fundamental concept in music. A good understanding of triads is useful in soloing, comping, composing and pretty much any other musical situation you might find yourself in.
Following on from looking at the major triads in open D, a next logical step is to look at minor triads.