Indo Aryan languages are all derivatives of Mother language Sanskrit - the most complete human language of this planet. These include almost all languages of Afghanistan, Pakistan, Balochistan, Kurdi communities in Iran, Iraq, Syria and Turkey, Armenia, Azerbaijan and some areas of Caspian.
Many languages that are in red like Prakrit, Gandhari, Vedda, Niya, Avestan, Scythian, Bactrian, Khotani, Khwarezmian, Saka, Sarmatian, Pamiri, Vanji, Old Persian, Mediani, Alanic, Sogdian, Parthian, Zaza Gorani are no longer in colloquial usage or rather extinct as they were originally known. Some of them may have corrupted into some colloquial usage among smaller communities that have been merged by force by Islamic influence that literally bulldozed hundreds of ancient communities and forced them to merge, disappear or be absorbed by invaders.
This branch includes two sub-branches: Indic and Iranian. Today these languages are predominant in India, Pakistan, Sri Lanka, Bengali communities, Tajikistan, Afghanistan, Blochistani communities Iran and its vicinity and also in areas from the Black Sea to western China.
Sanskrit, which belongs to the Indic sub-branch, is the best known among the early languages of this branch; its oldest variety, Vedic Sanskrit, is preserved in the Vedas, a collection of hymns and other religious texts of ancient India.
Now there are two theories. One says Indic speakers entered into the Indi subcontinent, coming from central Asia around 1500 BCE: In the Rig-Veda, the hymn 1.131 speaks about a legendary journey that may be considered a distant memory of this migration. My research, is that Sanskrit was the root mother language spoken around the great ancient India and its speakers expanded in entire Central Asia, Anatolia, Caspian, Mediterranean, Gulf of Arabia / Persia and to most Mediterr. coast and Egypt.
Avestan is a language that forms part of the Iranian group. Old Avestan (sometimes called Gathic Avestan) is the oldest preserved language of the Iranian sub-branch, the “sister” of Sanskrit, which is the language used in the early Zoroastrian religious texts. Another important language of the Iranian sub-branch is Old Persian, which is the language found in the royal inscriptions of the Achaemenid dynasty, starting in the late 6th century BCE. The earliest datable evidence of this branch dates back to about 1300 BCE. I will be posting more info on Avestan and its relation with Sanskrit shortly.
Today, many Indic languages are spoken in India and Pakistan, such as Hindi, Urdu, Punjabi, and Bengali. Iranian languages such as Farsi (modern Persian), Pashto, and Kurdish are spoken in Iraq, Iran, Afghanistan, and Tajikistan.
The Indo-Aryan or Indic languages are the key language family of the Indian subcontinent and South Asia. They constitute a branch of the Indo-Iranian languages, itself a branch of the Indo-European language family. Indo-Aryan speakers form about one half of all Indo-European speakers (about 1.5 of 3 billion), and more than half of all Indo-European languages recognized by Ethnologue. While the languages are primarily spoken in South Asia, pockets of Indo-Aryan languages are found to be spoken in Europe and the Middle East.
The largest in terms of native speakers are Hindustani (Hindi-Urdu, about 250 million), Bengali (about 200 million), Punjabi (about 100 million) Marathi (about 70 million), Gujarati (about 50 million), Rajasthani (about 50 million), Bhojpuri (about 40 million), Awadhi (about 38 million), Maithili (about 30 million), Odia (about 30 million), Sindhi (about 25 million), Braj Bhasha (about 21 million), Saraiki (about 20 million), Chhattisgarhi (about 18 million), Nepali (about 16 million), Sinhala (about 15 miilion), Assamese (about 15 million), Haryanvi (about 13 million), Kannauji (about 9 million), Bagheli (about 8 million), Kashmiri (about 6 million), Dogri (about 4 million), and Bundeli (abut 3 million), Garhwali (about 3 million), Kumaoni (about 2 million), with a total number of native speakers of more than 900 million. Dogri of Jammu Kashmir is same language spoken in Occupied Kashmir area where it is called Potohari/Potwari and also a variation called Hindko.