The familiar do-re-mi sound is the major scale. Many theory terms are measured against it, so understanding it makes chords and keys much easier.
A whole step equals two frets; a half step equals one fret. The major scale is a seven-note pattern that underlies much of Western melody and harmony. Its interval sequence is whole, whole, half, whole, whole, whole, half.
Formula
W–W–H–W–W–W–H.
Scale degrees have stable roles
The first degree is the tonic or root, the fifth creates strong support, and the seventh sits one semitone below the root and strongly pulls upward. Hearing those roles is more useful than only memorizing fret numbers.
Chords are built from its notes
Stacking alternate notes of a major scale produces the diatonic triads: major, minor, minor, major, major, minor and diminished. This is why common progressions in one key share a predictable family of chords.
Movable pattern
The interval formula stays the same in every key. Only the starting root changes.
The interval formula works from every root
Starting the same whole-step and half-step sequence from G produces G-A-B-C-D-E-F-sharp. The note names change, but the scale-degree roles and chord-quality pattern remain consistent.
Put the idea on the fretboard
- Memorise the whole- and half-step pattern.
- Play a one-octave C major scale and name C, D, E, F, G, A and B.
- Number the notes 1 to 7.
- Find the root in more than one place.
- Sing the scale before playing it.
- Pause on the seventh degree, B, then resolve to C and listen to the pull.
When the idea still feels confusing
You use only natural notes in every key
Some major keys require sharps or flats to preserve the interval pattern.
The scale shape sounds wrong over a chord
Confirm that the root and key match the backing harmony.
The pattern changes when you move strings
The B-string tuning interval shifts fretboard shapes. Follow note names and intervals so the musical pattern remains clear even when the visual layout changes.