Doesn't official Iranian language (Farsi) use the Western alphabet, rather than Arabic script? Just curious. Why are all the protesters' signs in Arabic?
No, Our alphabet is Persian and has nothing to do with Arabic!
Btw it is Persian not Farsi
http://heritage.chn.ir/en/Article/?id=88
Persian (Iranian) people in the English-speaking countries are the only community who use two different terms to refer to their language, “Farsi” and “Persian.” This behavior has caused some confusion among the Westerners as to the appropriateness of these terms.
“Farsi” (an Arabic adaptation of the word “Parsi”), is the indigenous name of the Persian language. Just as the German speaking people refer to their language as ‘Deutsch’, the Greek ‘Ellinika’ and the Spanish ‘Espanol’, the Persians use ‘Farsi’ or ‘Parsi’ to identify their native form of verbal communication.
In English, however, this language has always been known as “Persian” (‘Persane’ in French and ‘Persisch’ in German’). But many Persians migrating to the West (particularly to the USA) after the 1979 revolution continued to use ‘Farsi’ to identify their language in English and the word became commonplace in English-speaking countries.
In the West when one speaks of ‘Persian Language’, people can immediately connect it with several famous aspects of that culture and history such as Persian Gulf, Persian Carpet, Persian food, Persian poetry, Persian cat, etc. But “Farsi” is void of such link which is only obvious for people in Persia (Iran) and a few other nations in the Middle East.