Yesterday was Diwali, the Indian festival of lights. Diwali has been celebrated since ancient times and many different people have different opinions on its origin. The most well known story behind Diwali is in the Ramayana, a Hindu myth. According to Ramayana, Rama, Prince of Ayodhya was ordered by his father, King Dasharatha, to live in the forest for fourteen years. So Rama, his wife, Sita, and brother Lashmana left in exile. However Ravana, the demon king of Lanka abducted Sita and took her away to his island kingdom of Lanka. Rama fought against and killed Ravana, rescued Sita and returned to Ayodhya after fourteen years. The people of Ayodhya were so happy to hear of their prince's homecoming that they celebrated by lighting up their houses with earthen lamps (diyas), burst crackers and decorating the entire city beautifully.
This is believed to have started the tradition of Diwali. Year after year the homecoming of Lord Rama is commemorated on Diwali with lights, fireworks, bursting of crackers and merriment. The festival gets its name Deepawali, or Diwali, from the rows (avali) of lamps (deepa) that the people of Ayodhya lit to welcome their King.