Indo-Aryan is an ethno-linguistic term referring to the wide collection of peoples united as native speakers of the Indo-Aryan branch

Indo-Aryan languages

The Indo-Aryan languages constitutes a branch of the Indo-Iranian languages, itself a branch of the Indo-European language family...

 of the Indo-Iranian family

Indo-Iranian languages

The Indo-Iranian language group constitutes the easternmost extant branch of the Indo-European family of languages. It consists of three language groups: the Indo-Aryan, Iranian and Nuristani...

 of Indo-European languages

Indo-European languages

The Indo-European languages are a family of several hundred related languages and dialects, including most major current languages of Europe, the Iranian plateau, and South Asia and also historically predominant in Anatolia...

. Today, there are over one billion native speakers of Indo-Aryan languages, most of them native to South Asia

South Asia

South Asia, also known as Southern Asia, is the southern region of the Asian continent, which comprises the sub-Himalayan countries and, for some authorities , also includes the adjoining countries to the west and the east...

, where they form the majority.
The first people to have settled in India during Paleolithic times appear to have been an Australoid

Australoid

The Australoid race is a broad racial classification. The concept originated with a typological method of racial classification. They were described as having dark skin with wavy hair, in the case of Veddoids from South Asia and Aboriginal Australians, or hair ranging from straight to kinky in the...

 group who may have been closely related to Aboriginal Australians.