Should I learn triads on guitar?
Major triads are the building blocks of major chords. If you're used to playing only full chords, triads will help expand your playing and allow you to create more unique voicings and tones. They're a great way to spice up your playing by allowing you to easily add little embellishments to your rhythms.
How many guitar triads are there?
Eventually you will find that there are three triad shapes on each set of strings, and there are four sets of strings: 123, 234, 345, 456. That gives a total of 12 triad shapes to learn. The most important thing of course is that you make sure you learn which note in each shape is the root note.