Pongal is the name given for the Thanks Giving festival in Tamilnadu. The name of Harvest Thanks Giving festival in different states of India are:
Pongal - Harvest festival of Tamilnadu celebrated for four days and the new and feshly harvested rice is cooked with Jaggery and milk and offerred to Sun God. The Sun God is offerred with Sweet Pongal, Ven Pongal, Sugar Cane.
Makar Sankaranti - In most of the north Indian states people celebrate the harvest festival as Makar Sankaranthi and the main attraction of this celebration is the kite flying. Competitions and contests on kite flying and kite capturing goes on in many states.
Lohri - The harvest festival of Punjab is celebrated on the coldest day of the Lunar year. The celebration is performed with the traditional Bhangra dance around the fire. People offer sugarcane, rice and sesame seeds. Folk songs are sung as a thanks for giving a good harvest.
Bihi/Bohaggiyo Bhishu - The harvest festival of Assam and is one the biggest of the 3 Bihus that is celebrated. This festival is celebrated as the festival of cultivation of paddy which is the principal produce crop of Assam.
Hadaga Festival - This is the harvest and monsoon thanking festival of Maharashtra. People of Maharashtra pray to lord Indra. People sing songs to praise Indra and also draw the images of elephant which the mount of Indra to thank him for the rain.