Basic Western Music Theory

In this introduction to Western Music Theory we will cover the following topics:

  1. Musical Alphabet-Note Names
  2. Enharmonic notes-Why do we call a note a sharp or flat
  3. Musical steps
  4. The Major Scale
  5. The Minor Scale
  6. Musical Intervals

The Musical Alphabet

The Western Musical alphabet consists of 12 notes, A, A#, B, C, C#, D, D#, E, F, F#, G, and G#.  All notes labeled with #’s can also be express as flats(b) of the note above it. For example A# can be referred to as Bb, D# as Eb etc. Notes that share the same name are referred to as enharmonic notes.

Enharmonic Notes

The use of an enharmonic note is determined by the Key Signature (the parent key that the note belongs to). We will review this in further detail later but for now it's important to understand why common musical language uses a sharp or flat. Below is a chart of "Keys" and notes in that key.

Sharp Keys

D D,E,F#,G,A,B,C#
E E,F#,G#,A,B,C#,D#
G G,A,B,C,D,E,F#
A A,B,C#,D,E,F#,G#
B B,C#,D#,E,F#,G#,A#

Flat Keys

F F,G,A,Bb,C,D,E
Gb Gb,Ab,Bb,Cb,Db,Eb,F
Ab Ab,Bb,C,Db,Eb,F,G
Bb Bb,C,D,Eb,F,G,A
Cb Db,Eb,Fb,Gb,Ab,Bb,Cb
Db Db,Eb,Fb,Gb,Ab,Bb,Cb

Musical Steps

Notes that are positioned next to each other are referred to as half steps.  Half steps naturally  occur between the B and the C and E and F notes, whereas all other notes have a note (sharp or flat) in between them.  Look at the keyboard below for a visual clue how this works.

Whole steps occur when there is one note between two keys, for example in the keyboard above there are whole steps between C and D,  C# and D#, D and E, etc.

The Major Scale

Let's now look at one of the fundamental building blocks of Western Music Theory, the Major Scale. This is a diatonic (7 note) scale that begins again on its’ eighth note one octave higher. When learning basic scale theory we usually use the Key Of C as there are naturally no sharps or flats in its’ major scale. The chart below shows the Major Scale in the Key of C and includes the Note Name, Scale Step, Interval, Western Solfeggio syllables used in Sight Singing as well as the East-Indian Swara syllables. A further explanation of intervals follows the scale charts.

Scale Step 1 2 3 4 5 6 7 8
Interval Root Major 2nd Major 3rd Perfect 4th Perfect 5th Major 6th Major 7th Octave
Solfeggio Do Re Mi Fa So La Ti Do
Swara Sa Re Ga Ma Pa Da Ni Sa

One way scales are usually taught for memorization is to look at where the "half-steps" occur.  If we look at the above piano we will observe that there are no notes (black keys) in between the b & c, and e & f keys.  This is the same for all major scales, so if we think of the scale in terms of the numbered intervals, whole steps occur between the 1st & 2nd, 2nd & 3rd, 4th & 5th, 5th & 6th & 6th & 7th scale degrees.  Half-steps occur between the 3rd & 4th and 7th and 8th scale degrees.

The Minor Scale

The minor scale is another diatonic scale that is the other predominant scale in Western Music as well as theory.  The A minor scale shares the same notes as the C Major scale so we’ll use that as the root.

Scale Step 1 2 3 4 5 6 7 8
Interval Root Major 2nd Minor 3rd Perfect 4th Perfect 5th Minor 6th Minor 7th Octave
Solfeggio Do Re Me Fa So Le Ba Do
Swara Sa Re Komal Ga Ma Pa Komal Di Komal Ni Sa

Looking at this scale we see there are half steps between the 2nd and 3rd and 5th and 6th notes of the scale.


An interval in musical terms is the distance between two given notes.  Earlier I stated how two notes that are next to each other are a “half-step” apart, when two notes are directly next to each other they are referred to as a “minor second”.  Two notes that are two half steps apart from each other are also a “whole step” apart from each other and this interval is a Major Second. 4ths and 5ths are referred to as perfect intervals while 2nds, 3rds, 6ths and 7ths are referred to as major or minor. The chart below shows the 13 different types of intervals there are split up between the 8 different notes of the musical alphabet.

Unison 0 steps, same note
Minor Second (m2) 1/2 step
Major Second (M2) 1 whole step
Minor third (m3rd) 1 1/2 steps
Major Third 2 whole steps
Perfect Fourth (P4) 2 1/2 steps
Tri-tone (flatted 5th or raised 4th) 3 whole steps
Perfect 5th 3 1/2 steps
Minor Sixth (m6) 4 whole steps
Major Sixth (M6) 4 1/2 steps
Minor 7th 5 whole steps
Major 7th (M7) 5 1/2 steps
Octave (P8) 6 whole steps