as always - thanks so much for the great advice, examples, and links.

Now some related questions - I've read that it is very important for musicians to know the 'circle of 4ths' - or 'circle of 5ths'.

Now I have memorized it - pretty easy:
C F Bb Eb Ab Db Gb B E A D G...C F

My questions:
1.) what is the difference between the circle of 4ths and 5ths

2.) when you play the circles, do you do it with chord qualities of all majors, or all minors, or all 7ths ? If so, can you share some particular song examples

3.) what are some other ways to apply these circles directly into:
a.) transcribing songs
b.) your compositions

Am I even asking the right questions - do I 'know' what I 'don't know', or do I NOT know what I don't know lol