The 1964 Afghanistan Constitution names both Dari (an Afghan dialect of Farsi) and Pashto as the official languages. Dari literally means language of the court (dabar or dar; not darra, language of the valley) and is the lingua franca and is used for education and bureaucracy, though the Constitution designates Pashto as the national language.
A special committee appointed in 1964 aimed to promote the growth and spread of Pashto. During the 1953-63 ministry of Sardar Mohammad Daoud Khan, a disastrous attempt to Pashto-ize all government inter-office memoranda collapsed in a welter of translation and re-translation as non-Pashto-speaking high-ranking officials had their assistants convert paperwork back-and-forth.
Vocabulary differences occur between Dari dialects, but all are mutually understandable. The Wakhi and Pamiri have more difficult understanding their respective archaic Dari (Avestan) dialects, however. Pashto is not mutually intelligible with Dari and has nine phonemes unknown to Dari. Dari and Pashto are as different as English and German, or French and Spanish.
Within Nuristan, valleys just a few hours from each other may have different terms for such important designations as father, mother, brother and sister. This remarkable resistance to acculturation serves to perpetuate a society's cultural ethos. In contrast, scattered Moghol communities have become Persianized-- several old men in Turkabad in 1961 "deplored the fact that younger men became more Persianized with each generation, and most Moghol speak Farsi, even at home" (Dupree 2002, p 74).
Afghan farsi. Most rural Afghans still refer to the language as Farsi, not Dari.
Farsi with many Turkic loan words.
Related but not identical to Tajiki spoken in Tajikistan. Afghans refer to Tajiki by the valley in which it is spoken, such as Panjsheri, Andarabi, etc.
Farsiwan farmers of western Afghanistan speak Iranian Farsi.
Heratis have an urban dialect all their own.
Kabulis speak the slurred Brooklynese of Dari dialects.
A softer dialect found in the Qandahar area, in the southwest of Afghanistan.
Spoken in the southeast.
A harsher dialect spoken in Peshawar and the North West Frontier Province and most of the Tribal Agencies.
Spoken in the northeast.
Spoken in southwestern Afghanistan. The Brahui, Dravidian-speakers living amonghte Baluch, speak Baluchi as a second language using the South Indian language almost exclusively in the home.
Within Nuristan. Include several disparate group. Often each village or valley attaches a specific name to its dialect, such as Ormuri, Pashai, Deghani, Wamai, Waigali, Kami, Kati (Bashgalior Kamdeshi), Prasun (Vermir), Ashuni.
Turkic dialects concentrated north of the Hindu Kush among the Uzbek, Turkoman and Kirghiz. Dialects vary from group to group, but most are mutually intelligible. The closer the Uzbek are to Persian speakers, the more Persian words get incorporated into their language. Turkic languages of Afghanistan use the Arabic script. However, former SSR's have had their languages transposed into the Cyrillic alphabet.