Khas tribe, popularly known as Khashya, according to the 2015 constitution of Nepal are an Indo-Aryan ethno-linguistic group native to the Himalayan region of the Indian subcontinent, in what is now the South Asian country of Nepal, as well as the Indian states of Uttarakhand, Himachal Pradesh, West Bengal, Assam and Sikkim. Historically, Khas were the speakers of an ancient Khas language from the Indo-Aryan language family and the earliest recorded speakers of the Western Pahari languages. The large portion of the Indo-Aryan speakers throughout lower Himalayas were the Khas people. An intrusion of this tribe from the Western and Northwestern Himalayas into Central Himalayas is substantiated by the early linguistic evidences related to the Nepali language. They were also known as Parbatiyas/Parbates and are currently known as Paharis/Pahadis.. They were also referred to as Yartse in Tibet and are also known as Khasan by Bhotia people. The term Khas has now become obsolete, as the Khas people have adopted communal identities because of the negative stereotypes associated with the term Khas. In Nepal the native speaker of Nepali language are known as Khas people.

Nepali is an Indo-Aryan language native to the Himalayas region of South Asia. It is the official, and most widely spoken, language of Nepal, where it also serves as a lingua franca. Nepali has official status in the Indian state of Sikkim and in the Gorkhaland Territorial Administration of West Bengal. It is spoken by about a quarter of Bhutan's population. Nepali also has a significant number of speakers in the states of Arunachal Pradesh, Assam, Himachal Pradesh, Manipur, Meghalaya, Mizoram and Uttarakhand. In Myanmar it is spoken by the Burmese Gurkhas. The Nepali diaspora in the Middle East, Brunei, Australia and worldwide also use the language. Nepali is spoken by approximately 19 million native speakers and another 14 million as a second language.