The Avestan alphabet was created in the 3rd century CE for writing the hymns of Zarathustra (a.k.a Zoroaster). Avestan is an extinct Indo-Iranian language related to Old Persian and Sanskrit. Many of the letters are derived from the old Pahlavi alphabet of Persia, which itself was derived from the Aramaic alphabet. Greek influence, in the form of the full representation of vowel sounds, is also present.
The Avestan alphabet was replaced by the Arabic alphabet after Persia converted to Islam during the 7th century CE.
The alphabet is written from right to left, in the same way as Syriac, Arabic and Hebrew.