Guitar chords in the key of C minor:
Cm Ddim Eb Fm Gm Ab Bb   G G7 Bbdim

Chord Cm (3rd fret) notes: (G), C, G, C, Eb and G.

This chord is played by placing a barre on fret three with your index finger. The note G on the sixth string is not required, but can be played on the 3rd fret if needed.

C minor chord's alternative names:
Cmin, C-, (Do minor, C moll).

Steps: 1-b3-5.
1(C), b3(D#/Eb), 5(G).