Avestan alphabet
The Avestan alphabet (Middle Persian: "dyn' dpywryh", "dēn dēbīrē", ) is a writing system developed during Iran's Sassanid era (226–651 CE) to render the Avestan language. As a side effect of its development, the script was also used for Pazend, a method of writing Middle Persian that was used primarily for the "Zend" commentaries on the texts of the Avesta. In the texts of Zoroastrian tradition, the alphabet is referred to as "the religion's script" ("dēn dibīrih" in Middle Persian and "din dabireh" in New Persian). History. The development of the Avestan alphabet was initiated by the  need to represent recited Avestan language texts correctly. The various text collections that today constitute the canon of Zoroastrian scripture are the result of a collation that occurred in the 4th century, probably during the reign of Shapur II (309–379). It is likely that the Avestan alphabet was an "ad hoc" innovation related to this – "Sassanid archetype" – collation. The enterprise, "which is indicative of a Mazdean revival and of the establishment of a strict orthodoxy closely connected with the political power, was probably caused by the desire to compete more effectively with Buddhists, Christians, and Manicheans, whose faith was based  on a revealed book". In contrast, the Zoroastrian priesthood had for centuries been accustomed to memorizing scripture — following by rote the words of a teacher-priest until they had memorized the words, cadence, inflection and intonation of the prayers. This they passed on to their pupils in turn, so preserving for many generations the correct way to recite scripture. This was necessary because the priesthood considered (and continue to consider) precise and correct enunciation and cadence a prerequisite of effective prayer. Further, the recitation of the liturgy was (and is) accompanied by ritual activity that leaves no room to attend  to a written text. The ability to correctly render Avestan did, however, have a direct benefit: By the common era the Avestan language words had almost ceased to be understood, which led to the preparation of the "Zend" texts (from Avestan "zainti" "understanding"), that is commentaries on and translations of the canon. The development of the Avestan alphabet allowed these commentaries to interleave quotation of scripture with explanation thereof. The direct effect of these texts was a "standardized" interpretation of scripture that survives to the present day. For scholarship these texts are enormously interesting since they occasionally preserve passages that  have otherwise been lost. The 9th–12th century texts of Zoroastrian tradition suggest that there was once a much larger collection of "written" Zoroastrian literature, but these texts — if they ever existed — have since been lost, and it is hence not known what script was used to render them. The question of the "existence" of a pre-Sassanid "Arsacid archetype" occupied Avestan scholars for much of the 19th century, and, "[w]hatever may be the truth about the Arsacid Avesta, the linguistic evidence shows that even if it did exist, it can not have had any practical influence, since no linguistic form  in the Vulgate can be explained with certainty as resulting from wrong transcription and the number of doubtful cases is minimal; in fact it is being steadily reduced. Though the existence of an Arsacid archetype is not impossible, it has proved to contribute nothing to Avestan philology." Genealogy and script. The Pahlavi script, upon which the Avestan alphabet is based, was in common use for representing various Middle Iranian languages, but was not adequate for representing a religious language that demanded precision since Pahlavi was a simplified abjad syllabary with at most 22 symbols, most of which were ambiguous (i.e.  could represent more than one sound). In contrast, Avestan was a full alphabet, with explicit characters for vowels, and allowed for phonetic disambiguation of allophones. The alphabet included many characters ("a", "i", "k", "t", "p", "b", "m", "n", "r", "s", "z", "š", "x") closely resembling Book Pahlavi of the early Islamic Persia, while some ("ā", "γ") are characters that only exist in the older (6th-7th c. AD) Psalter Pahlavi script (in later cursive Pahlavi "γ" and "k" have the same symbol). Some of the vowels, such as "ə" appear to derive from Greek cursives. Avestan "o" is a special form  of Pahlavi "l" that exists only in Aramaic signs. Some letters (e.g. "ŋ́", "ṇ", "ẏ", "v"), are free inventions. Avestan script, like Pahlavi script and Aramaic script also, is written from right to left. In Avestan script, letters are not connected, and ligatures are "rare and clearly of secondary origin". Letters. In total, the Avestan alphabet has 37 consonants and 16 vowels. There are two main transcription schemes for Avestan, the newer orthography used by Karl Hoffmann and the older one used by Christian Bartholomae. Later, when writing Middle Persian in the script (i.e. Pazend), another consonant was added to  represent the /l/ phoneme that didn't exist in the Avestan language. Ligatures. Four ligatures are commonly used in Avestan manuscripts: U+200C ZERO WIDTH NON-JOINER can be used to prevent ligatures if desired. For example, compare (U+10B31 10B00) with (U+10B31 200C 10B00). Fossey lists 16 ligatures, but most are formed by the interaction of swash tails. Digits. Digits and numbers can be seen on the Faulmann chart above. Punctuation. Words and the end of the first part of a compound are separated by a dot (in a variety of vertical positions). Beyond that, punctuation is weak or non-existent  in the manuscripts, and in the 1880s Karl Friedrich Geldner had to devise one for standardized transcription. In his system, which he developed based on what he could find, a triangle of three dots serves as a colon, a semicolon, an end of sentence or end of section; which is determined by the size of the dots and whether there is one dot above and two below, or two above and one below. Two above and one below signify — in ascending order of "dot" size — colon, semicolon, end of sentence or end of section. Unicode. The Avestan alphabet was added  to the Unicode Standard in October, 2009 with the release of version 5.2. The characters are encoded at U+10B00—10B35 for letters ("ii" and "uu" are not represented as single characters, but as sequences of characters) and U+10B38—10B3F for punctuation.