Stacking 3rds builds most of the chords of modern music. Of course not all chords are based on intervals of a 3rd. Some are based on 4ths as well as other intervals.
Types of chords built on thirds
- Major
- minor
- 7th
- Major 7
- min7
- 9th
- m9
- add 9
- 11th
- 13th
- Diminished
- Augmented
- And many more….