Standard Western musical notation utilizes a set of parallel horizontal lines called a staff to graph the approximate relationships of pitch-height of periodic sounds.
A "clef" is used to designate one particular line as a certain pitch, and all other nominals are mapped in ascending and descending order to the lines and spaces above and below that reference line.
The traditional 5-line staff does not visually recognize the periodicity of octave-equivalence, but some other designs do, such as Joe Monzo's 12-edo-staff and quarter-tone-staff notations.
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