Salford Piano Studio
A semitone is a musical term we use for a half-step, it is the note immediately above or below.
For example, the black note immediately above C is C sharp.
As you can see, in most cases the note immediately above is a black key. However, the two exceptions are E-F, and B-C.
A semitone up from E is F. There’s no black key between E and F (a gap).
What Is A Whole Tone?
A Whole tone, also a Whole Step or Tone, is the equivalent of two semitones.
For example, the distance between C and D. (Skipping the black key in between)
Similarly, the distance between these two black keys is a Whole Tone (skipping the white key in between)
Here is a full scale from C to C.
As you can see, the naturals are mostly Tones (T) with two exceptions of Semitones (S).
Tone – Tone – Semitone – Tone – Tone – Tone – Semitone