Chord Cheat Sheet
Understanding how chords work can be really confusing. But these four words can simplify all the theory into a simple concept: stack notes into 3rds.
The whole basis of harmony is built from this concept, starting from the simple and humble triad, right up to the more advanced 9th and 13th chords.
The cheat sheet below gives you a clear visual reference for stacking notes into chords. You can use it for identifying or creating chords. Developing your fluency of thinking in 3rds makes handling chords much easier.