Scientific pitch notation creates a linear pitch space in which an octave spans 12 semitones, where each semitone is the distance between adjacent keys of the piano keyboard. Distance in this space corresponds to musical pitch distance in an equal-tempered scale; 2 semitones being a whole step, 1 semitone being a half step. An equal-tempered semitone can also be subdivided further into 100 cents. Each cent is semitone or octave. This measure of pitch allows the expression of "microtones" not found on standard piano keyboards. The notation is sometimes used in the context of meantone temperament, and does not always assume equal temperament
Sicilian octave Renaissance and has seldom been used in English except as an illustration of the form. Before the 15th century, however, it was used often by poets in southern Italy, and was an important influence for Petrarch in his sonnets. Boccaccio, who popularized and may have invented the unrelated ottava rima, used the Sicilian octave a total of once, in his early romance Filocolo. The epitaph of Giulia Topazia is a Sicilian octave: Sicilian octave The Sicilian octave (Italian: "ottava siciliana" or "ottava napoletana", lit. "Neapolitan octave") is a verse form consisting of eight lines of eleven syllables each, called a