The Indian light festival Diwali is traditionally lit up by huge numbers of Diya (plural "diyas"). Diya is a contracted form of deep or light given by small earthen pots (also known as Pradeep and Deepak), with wick made of cotton and dipped in ghee. They are also used for praying to the deceased ancestors and are floated on leaves over the holy rivers like the Ganges at Haridwar.