C#/Db is a half step above C.
augmented
augmented
B flat. I picture it on the piano, one key is one semi-tone or half a tone. Two of these makes one whole tone, or one whole step. One half step down from C would be the note B, another half step would then go to B flat. That is one whole step.
C Natural is a whole step above B flat. If you look at a piano, a half step above B Flat is B Natural, and one more half step above that is C Natural. So it's a whole step from B Flat to C Natural.
It's a perfect interval that is called a diminished interval when reduced by half step; there is no such thing as a perfect note. Minor intervals are also called diminished intervals when reduced by half step. If you listen to a perfect fourth and a diminished fourth, for example, they clearly have very different sounds, so they need different names.
One quarter tone is half of a half step. They aren't used in Western music hardly at all, but you can find them in the Middle East.
It's called a "first". Actually there is no interval, because it is the same note. Consider it the interval nº 0. There is such a thing as a quarter tone, which is half of a half step, but they aren't used in Western music hardly at all. They are, however, prevalent in the Middle East.
An interval is the distance between two pitches. These intervals are measured in half-steps and whole steps. For example, a half-step is like C to Db. A whole step would be C to D. A major scale is made up of these steps as so: C MAJOR Whole step, Whole step, Half step, Whole step, Whole step, Whole step, Half step. C to D, D to E, E to F, F to G, G to A, A to B, B to C WWHWWWH You may have noticed that from E to F and from B to C it was a half step just as if it were from C to Db. This is because these pitches are simply a half step away from each other.
Tone Cluster
tone clusters
tone cluster APEX
A half step is a half step. It is also called a minor third. There is no "major" when it comes to half steps. If you meant the half steps on white keys on a keyboard, then that would be B-C and E-F.
The interval from A to Bb is a minor 2nd, also called a half step.
That is commonly called a half step.
The symbol to lower a note a half step is called a flat.
whole step, whole step, half step, whole step, whole step, whole step, half step