These reached the heights of popularity, and are considered by many considered to be masterpieces, although in the view of the skeptics gravitated dangerously toward salonism. They were included, along with the nocturnes and impromptus, to Chopin's "feminine" works. In the descriptions of their nature appear: volatility, airiness, overwheleming movement, aristocracy, eroticism. They are divided into two trends: social and concert.