Legend says that King Hiranyakashyap, an egoistic king had declared himself god and demanded his subjects to only worship him. His son, Prahlad, who was a great devotee of Lord Vishnu denied his demands of being worshiped as a god. Hiranyakashyap tried various trick to kill his son, but failed. In anger, he sent his sister Holika, who had the ability to walk in and out of fire unscathed, to kill Prahlad. Holika built a large pyre of fire and sat in the middle with Prahlad in her lap. As the pyre was lit, Prahlad kept chanting Lord Vishnu’s name and came out of it unharmed while Holika was burnt to death. This is celebrated as Holika Dahan, a day prior to Holi where people build a pyre and set it afire to commemorate this event, signifying victory of good over evil.