Final answer:
A scale composed completely of half steps is called a chromatic scale. The chromatic scale is distinctive as it encompasses all twelve notes within an octave, with each note being a half-step apart.
Step-by-step explanation:
A scale that is comprised entirely of half steps is called a chromatic scale. In music, a half step, also referred to as a semitone, is the smallest difference in pitch that the human ear can discern. Therefore, a chromatic scale, which comprises all twelve notes within the octave, each a half step apart, is unique in its ability to express every possible musical note in the octave vision.
For example, if you were to start on a piano with the note C and play every single note (both white and black keys) up to the next C, you would have played a chromatic scale. This is contrasted with a diatonic scale, which has a mix of whole steps and half steps, and a microtonal scale, which breaks down the octave into more than 12 pitches.
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