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
Steps and skips step will always be a movement of 1 or 2 semitones, and a skip a movement of 3 or more semitones. In other scales an augmented second—an incomposite step equivalent to 3 semitones—and/or a diminished third—a skip of 2 semitones—may be possible. Melody may be characterized by its degree and type of conjunct and disjunct motion. For example, Medieval plainchant melodies are generally characterized by conjunct motion with occasional thirds, fourths, and generally ascending fifths while larger intervals are quite rare though octave leaps may occur between two separate phrases. Renaissance melodies are generally characterized by conjunct motion, with only