Pashto is a member of the southeastern Iranian branch of Indo-Iranian languages spoken in Afghanistan, Pakistan and Iran. The name Pashto is thought to derive from the reconstructed proto-Iranian form, parsawā 'Persian language. In northern Afghanistan speakers of Pashto are called Pakhtūn; in southern Afghanistan they are known as Pashtūn, and as Pathān or Afghan in Pakistan. About poet or writer.. I really have no idea.. Hope these information helped.

Well, it is correct that Pashto is an Indo-Iranian language but this must be wrong that its name is derived from Persian. The word Pashto is taken from a tribal name "Pakts", an Arian tribe mentioned in Rigveda. There is still names of places like Paktia, Pakika and so on in Afghanistan. About 60 million people speaking on Pashto as a native language. This first poet whose poem is documented is Amir Kror.