The picture above is of a wycinanka -- cut out from colored paper, which is first folded several times to give a symmetrical effect. This type of folk art, sometimes referred to as "Polish origami" is practiced in several regions of Poland, with traditional designs and colors varying widely.
Polish folk art is extremely rich. One of its more popular manifestations are the pisanki -- Easter eggs which come in a myriad of designs and colors, dependent on the artist's imagination which gives endless variations on the time-honored traditional designs.
Check out the Polish Art Center for more details on these forms of traditional Polish folk art!
If you are wondering why the Chopin composition has been included among the examples of Polish folk culture, listen to a bit of the classical music and then wathc this folk ensemble Śląsk dance and sing the Krakowiak folk dance on the center square of Kraków. It will be immediately clear that Polish folk culture echoes throughout all of Polish art, including classical music.
Pictured above is the festival of water fights, Śmigus Dyngus. It is a folk tradition that is still observed on Easter Monday. In its current form it is basically a national water fight day. As you can see from the picture, the ritual is often performed with gusto.
This couple, dressed in the traditional dress of the górale, people of the Tatra mountains are dancing at a folk festival. However, it is very probable that they would wear their traditional dress on holidays (both church and national), and other formal social gatherings, such as these wedding guests in Zakopane.
For more on the Polish folk fashion, check out culture.pl!