The Major Scale
The one small thing to memorize about the major scale — and how it shows you where every natural note sits on the guitar neck.
There is a half step between E and F, and a half step between B and C.
Every other step is a whole step.
C major is built from natural notes only — no sharps, no flats — so those are the only two places a half step falls: from the 3rd note to the 4th, and from the 7th up to the 8th. Learn where E–F and B–C sit and the whole scale is spaced for you.
W is a whole step, H a half step — the nearest note with nothing in between. On a keyboard the half steps are plain to see: E–F and B–C are the only white keys with no black key between them. Every other step skips a black key.
Whole, whole, half — whole, whole, whole, half. That spacing is the major scale; keep it from any starting note and you’ve built that note’s major scale.
On the guitar a half step is one fret and a whole step is two. Take the open E string: start on E and move up by the same map — H (one fret) only from E–F and B–C, W (two frets) everywhere else. You land on E F G A B C D E, every natural note (the “white keys”) on that string, at frets 0, 1, 3, 5, 7, 8, 10 and 12. Because you start from E rather than C the half steps land in different places — but always between E–F and B–C. Every string works the same way: start from its open note (E A D G B E) and follow the map.
Start on any note other than C and you’ll need a sharp or flat here and there to keep the spacing exact — that is where key signatures come from. (See the diatonic-chords sheet.)