@af6bf358 - you get a circle of fifths if you move up the red arrows.   Each circle of fifths includes all 12 notes.

You get a circle of major thirds if you move along the blue arrows - but each circle of major thirds includes only 3 notes, e.g.

C E G# C E G# ...

And you get a circle of minor thirds if you move along the red arrows - but each circle of minor thirds includes only 4 notes, e.g.

C E♭ F♯ A C E♭ F♯ A .... 

 @b4c50e1b @af6bf358 "And you get a circle of minor thirds if you move along the s/red/black/ arrows... " 

 @272b0b05 - right, thanks!  Fixed.

 @af6bf358