The Lamaistic tradition of Mahayana Buddhism. Culturally similar to them are Membas and Khambas who live in the high mountains along the northern borders of Upper Siang and West Siang. The Khamptis and the Singphos, inhabiting the eastern part of the state ,are Buddhists of Hinayana sect. They are said to have migrated from Thailand and Burma long ago. The Zakhrings of the Lohit Valley are influenced by Buddhism of Mahayana sect. They have migrated from Zeyus in Tibet. They are characterized by their expertise of carpet making, weaving, dancing, painting, mask -making and elaborate dresses. The second group consists of the Nyishis, the Apatanis, the Adis, the Mishmis, the Tagins, the Mijis, the Akas, the Sulungs (Puroik) and the Khowas. The religion of this group can be termed as animistic-naturalistic. They worship natural objects and ancestors. The Tani group of people - the Apatanis, the Nyishis, the Adis, the Galos and the Tagins worship Sun (Donyi) and Moon (Polo). These tribes are excellent in weaving and fine works of cane and bamboo. The third group comprises the Noctes, the Tangsas, and the Wanchoos of Tirap and Changlang districts. These tribes are known for their masculine dances, and art of woodcarving. They have been known for their association with the practice of headhunting and their contacts with Burmese tribes. The festivals, marked by elaborate rituals and dances, form an essential element of the socio-cultural life of the people. Some of the important festivals are Mopin of the Galos, Solung of the Adis, Losar of the Monpas, Dree of the Apatanis, Si-Donyi of the Tagins, Nyokum of Nyishis and Reh of the Idu Mishmis. All the languages of the tribes of Arunachal Pradesh except Khamtis belong to "Tibeto-Burman family". The Khampti language belongs to Tai group of the Chinese Siamese family. English is the official language of the state. Hindi and Assamese serve as the lingua franca in absence of a commonly accepted language for all the tribes.