The key of C major is the easiest key to get to know.
This article deals with it’s principles, key signature, chords, relative minor and modes.
It also contains links to related articles on this site.
First the key signature.
This bit is the easiest bit.
When you look at the clef, you will see no sharps or flats indicated.
This is because the key of C has none.
The C Major scale has the following notes: C D E F G A B
The Key of C has the following chords: C Dm Em F G Am Bdim
It’s relative Key is A Minor.
It’s Modes are:
A Aeolian(natural minor)
Popular Chords from C major – excluding diminished chords: