Standard Tibetan is the most widely spoken form of the Tibetic languages. It is based on the speech of Lhasa, an Ü-Tsang (Central Tibetan) dialect. For this reason, Standard Tibetan is often called Lhasa Tibetan. Tibetan is an official language of the Tibet Autonomous Region of the People's Republic of China. The written language is based on Classical Tibetan and is highly conservative.