Holi is a religious spring festival celebrated by Hindus. Holi is also known as festival of Colours.
Though there have been references to a festival like this in Sanskrit texts like ratnavali where people sprayed coloured waters using bamboo syringes,the origin of the modern Holi festival has been traced to ancient Bengal. It was a Gaudiya Vaishnav festival, in accordance to Vaishnaviya Tantra. People went to Krishna temples, applied red colour to the icon and then distributed the red coloured powder or Abir along with malpua prasad to family and friends. Red signified the colour of passion and Lord Krishna is the king of desires. The ritual signified that all our desires should be diverted for the attainment of Krishna and for the well being of society.
In some cultures though,the ritual of burning wood and leaves on the full moon night already existed. This ritual was to signify the end of winter and full advent of spring. Old wood and leaves that had fallen were burnt to signify that it is time for new leaves and flowers.People later smeared their bodies with ash. Later, however, the story of Holika Dahan has been associated with this ritual.
The legend on King Hiranyakashipu is one of the explanations Hindus look back to. The King condemned his son, Prahlad, from worshipping the god Vishnu. However, he continued to pray to him. Filled with anger, the King made a challenge to his son. He was to sit on a pyre along with his aunt Holika, believed to be unharmed by fire. The son accepted the challenge, praying to Vishnu to protect him. As the fire began, Holika was burnt to a crisp but Prahlad lived and was unharmed. This burning of Holika is the reason why Holi exists.