In that case, also known as "speed dancing" (because of its similarities to speed dating), the DJ picks two people to start dancing, usually to a slow dance. Periodically the DJ will shout, "snowball," signaling that the dancers must find new partners, thus increasing the number of partners on the floor. Half of the people asking new dancers to come to the floor will be girls asking boys, Sadie Hawkins-style. By the end of the song, most of the people at the dance are on the dance floor. The "snowball dance" is typically used to get the dancing started, as school dances can be notoriously slow to start. In some areas, people chosen to dance cannot refuse, thereby ensuring people get onto the dance floor, and thus the "snowball" gains momentum and grows.