Linked from
The 10 pages that link to Persian alphabet, each with the reason it gives.
Persian languageRelated: Modern Persian in Iran and Afghanistan is written in this adapted script.
Arabic scriptBroader topic: Persian writing adds letters absent from the Arabic inventory.
New PersianBroader topic: Its added letters accommodate sounds absent from standard Arabic.
Urdu alphabetRelated: Persian writing transmitted many conventions and letter forms into Urdu.
NastaliqRelated: Nastaliq arranges Persian letters into its characteristic sloping lines.