Originally Posted by: Ish.RiveraI have always assumed that the Do Re Mi nomenclature came first and the ABC's second.

"Do Re Mi" is called solfege. This wiki page contains info on it's origin & history:

http://en.wikipedia.org/wiki/Solfege

For our purposes here, "Do Re Mi" refers to the notes of any & all major scales. So "Do" can be any of the 12 possible chromatic music notes (A through G#). It's merely the formula you apply once you decide on a starting note.

So, it can line up with the notes from the C major scale:

C (do) 1st
D (re) 2nd
E (mi) major 3rd
F (fa) 4th
G (so) 5th
A (la) major 6th
B (ti) major 7th
C (do) 8th

Likewise, if you put the Do on D it can line up with the notes from the D major scale:

D (do) 1st
E (re) 2nd
F# (mi) major 3rd
G (fa) 4th
A (so) 5th
B (la) major 6th
C# (ti) major 7th
D (do) 8th

And so on with all the possible letters! I discuss major scales (and mention solfege) in the GF2 course, Intro to C major scale for beginners tutorial:

http://www.guitartricks.com/tutorial.php?input=363

Hope this helps! Have fun. :)