This year was the 20th anniversary of the event, originally the first street painting festival in North America, which benefits the Children's Creative Project. As described on the festival's website:
Street painting has a long tradition in cities in Western Europe and probably started in Italy in the 16th century. The artists who use chalk to draw on the street are known as "madonnari" or "Madonna painters" because they reproduced icons of the Madonna, (our lady). The works are traditionally called street paintings, rather than chalk drawings or sidewalk art, because when well executed they can resemble paintings. The artists would travel from town to town and create street paintings for traditional religious and folk festivals. These artists lived (and still live) from the coins thrown onto their work in appreciation for the image and the artist's skill.