Language spoken principally in Iran and Afghanistan. Persian belongs to the Iranian branch of the Indo-Iranian language family.
Old Persian
Old Persian was contemporary to Avestan, another Old Iranian language. Old Persian is preserved through cuneiform tablets found in the remains after the Achaemenid dynasty (550- 330 BCE). The oldest traces of Old Persian date to the 6th century BCE, but it was spoken until the 3rd century BCE.
Old Persian was spoken in southwestern Iran, while Avestan was spoken in northeastern Iran. In addition to the two languages there must have been at least a third. Median is mentioned by the Greek historian Herodotus.
It is believed that there must have been a fair level of mutual intelligibility between the Iranian languages of this period, and more than there would be in later periods.
Middle Persian
Middle Persian was a contemporary of Parthian, and during the Arsacid period, Persian was strongly influenced by Parthian. Middle Persian was the language used in the Sassanian Empire, and was called Pahlavi.
Middle Persian was, just like Old Persian, spoken in southwestern Iran, Parthian was spoken in the north, while a group of languages (Khwarezmian, Sogdian and Saka) were spoken in southeast.
The grammar of Middle Persian was simpler than in Old Persian. The script used was one of ambiguous script with multivalent letters, derived from Aramaic.
Middle Persian would last until the 9th century CE, even if its decline came with the introduction of Arabic already two centuries earlier.
Modern Persian
Modern Persian, the language of Iran today, was developed as early as in the 9th century. It was in many fields a continuation of Middle Persian, but there were important influences coming from other Iranian languages.
Modern Persian used an expanded form of Arabic writing, introducing letters like ch, p, zh, g, and changing the pronunciation of Arabic zh into "za". There is also a large selection of Arabic words in Modern Persian, exceeding 40%.
The grammar of Modern Persian is simpler than the one of Middle Persian (just like Middle was simpler than Old Persian). Most of the inflectional systems are lost, and there is no system of case inflection. Possession is shown by a suffix called ezafeh. Tense, mood, voice and negative are likewise indicated by a series of prefixes and infixes (word elements inserted inside a word).
