The C5 chord (power chord): notes C G, degrees 1 – 5. Guitar shapes: x355xx, 8-10-10-x-x-x, x-x-10-12-13-x, x-x-10-12-x-x.
A chord is the root plus degrees above it, most often stacked in thirds. Major and minor differ only in the lower third: a major third (M3) sounds bright, a minor third (m3) sounds sad. Pick a chord and a root to see its degrees and intervals, and its shapes.
m — minor, M — major, P — perfect, A — augmented interval; the number is the degree count. m3 is 3 semitones, M3 is 4, P5 is 7
C Cm C5 C7 Cm7 Cmaj7 Csus2 Csus4 Cadd9 C6 Cm6 C9 Cdim Cdim7 Cm7♭5 Caug