Nepali or Nepalese is an Indo-Aryan language. It is the official language and de facto lingua franca of Nepal and is also spoken in India, Bhutan and Burma. Nepali has official status in the Indian state of Sikkim and in West Bengal's Darjeeling district. Nepali developed in proximity to a number of Indo-Aryan languages, most notably the Pahari languages and Magahi, and shows Sanskrit influences. However, owing to Nepal's geographical area, it has also been influenced by Tibeto-Burman. Nepali is mainly differentiated from Central Pahari, both in grammar and vocabulary, by Tibeto-Burman idioms owing to close contact with the respective language group. Nepali language shares 40% lexical similarity with Bengali language.