[7] It is a set of spoken and written formal varieties used by the educated persophones of several nations around the world.

The standard forms of the three are based on the Tehrani, Kabuli, and Bukharan varieties, respectively.

[9][10] The Persian alphabet is used for both Farsi (Iranian) and Dari (Afghan).

Traditionally, Tajiki is also written with Perso-Arabic script.

Later in the late 1930s, the Tajik Soviet Socialist Republic promoted the use of Cyrillic alphabet, which remains the most widely used system today.