Bartók's Mikrokosmos holds a place unique in pianoforte literature. Its achievement lies far beyond that of the conventional course of progressive studies. From the earliest exercises, consistent use is made of the ecclesiastical modes, which often supplant the diatonic scale, and a real extension of tonal awareness is thus offered from the most elementary stages; the student is also familiarised with unusual time-signatures and rhythmic structures, while to the student of composition valuable insight into technical procedures is offered in a particularly clear form. And a use of the rhythms and melodies of folk music is of great value as documenting (accessibly) the constituents of Eastern European peasant song and dance.