In Western music, the octave is divided into twelve notes. Seven of these notes are called ‘naturals’: C – D – E – F – G – A – B’. The other five notes are referred to as ‘accidentals’, sharps (denoted by ‘#’) or flats (denoted by ‘b’). Simply put, an interval is the difference in pitch between two notes.

A sharp note is one semitone higher in pitch than a natural note. For example, the distance between C and C# is one semitone (or one half step).

A flattened note is one semitone lower in pitch than a natural note. Let’s look at the notes B and Bb. The distance between these notes equals one semitone.
Sometimes there are multiple names for notes that are identical in pitch. For instance, the notes A# and Bb are the same notes, just as C# and Db, D# and Eb, and so on. Thus, you could say that the notes A# and Bb are enharmonically equivalent. These are referred to as ‘enharmonics’.

Accidentals (sharps and flats) are not found between every note. Note that between ‘B – C’ and ‘E – F’ there are no accidentals. On the piano, you will see that there are no black keys between these notes. As such, the interval between these notes equals one semitone or one half step.
In the picture below, the twelve notes are shown on the piano.

 The interval between any note and an adjacent note is one semitone.

Why should you know intervals? Intervals are used to build scales. In the next theory lessons we will explain how you can use intervals to build scales, as well as different types of chords. Do you still have any questions? Free to ask them in the comments below. And if you are ready to deepen your understanding of music theory – visit our shop to find the Wheel of Fifths Songwriting Tool. Stay tuned for more!

Comment 1

Ethan on

This is the first time that I’ve read an explantion of naturals and accidentals, that’s actually made sense to me!
Thank you! 😁

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