Chords: stacking notes to paint moods

A chord is two or more notes sounding at the same time. The simplest and most common chords are triads - three notes stacked in thirds.

In C major, the home chord is C-E-G (C major triad). Skip every other note up the scale.

Those three chords - I, IV, V (one, four, five) - are the engine room of more songs than you can count. Pop, blues, country, gospel, reggae - all lean heavily on them.