Nepali or Nepalese (नेपाली), is a language in the Indo-Aryan languages. It is the official language and de facto lingua franca of Nepal and is also spoken in Bhutan. Nepali has official language status in the formerly independent state of Sikkim and in West Bengal's Darjeeling district. Nepali developed in proximity to a number of Indo-Aryan languages, most notably Pahari and Magahi, and shows Sanskrit influences. However, owing to Nepal's geographical area, the language 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.
Historically, the language was first called the Khas language (Khas kurā), then Gorkhali or Gurkhali (language of the Gorkha Kingdom) before the term Nepali (Nepālī bhāṣā) was taken from Nepal Bhasa. Other names include Parbatiya ("mountain language", identified with the Parbatiya people of Nepal) and Lhotshammikha (the "southern language" of the Lhotshampa people of Bhutan). (Wikipedia)