Kurdish (, ) is a language or a group of languages spoken by Kurds in the geo-cultural region of Kurdistan and the Kurdish diaspora. Kurdish constitutes a dialect continuum, belonging to Western Iranian languages in the Indo-European language family. The main three dialects or languages of Kurdish are Northern Kurdish (), Central Kurdish (), and Southern Kurdish (). A separate group of non-Kurdish Northwestern Iranian languages, the Zaza–Gorani languages, are also spoken by several million ethnic Kurds. The majority of the Kurds speak Kurmanji, and most Kurdish texts are written in Kurmanji and Sorani. Kurmanji is written in the Hawar alphabet, a derivation of the Latin script, and Sorani is written in the Sorani alphabet, a derivation of Arabic script. The classification of Laki as a dialect of Southern Kurdish or as a fourth language under Kurdish is a matter of debate, but the differences between Laki and other Southern Kurdish dialects are minimal. The literary output in Kurdish was mostly confined to poetry until the early 20th century, when more general literature became developed. Today, the two principal written Kurdish dialects are Kurmanji and Sorani. Sorani is, along with Arabic, one of the two official languages of Iraq and is in political documents simply referred to as "Kurdish". Classification and origin The Kurdish languages belong to the Iranian branch of the Indo-European family. They are generally classified as Northwestern Iranian languages, or by some scholars as intermediate between Northwestern and Southwestern Iranian. Martin van Bruinessen notes that "Kurdish has a strong South-Western Iranian element", whereas "Zaza and Gurani [...] do belong to the north-west Iranian group". Ludwig Paul concludes that Kurdish seems to be a Northwestern Iranian language in origin, but acknowledges that it shares many traits with Southwestern Iranian languages like Persian, apparently due to longstanding and intense historical contacts. Windfuhr identified Kurdish dialects as Parthian, albeit with a Median substratum. Windfuhr and Frye assume an eastern origin for Kurdish and consider it as related to eastern and central Iranian dialects. The present state of knowledge about Kurdish allows, at least roughly, drawing the approximate borders of the areas where the main ethnic core of the speakers of the contemporary Kurdish dialects was formed. The most argued hypothesis on the localisation of the ethnic territory of the Kurds remains D.N. Mackenzie's theory, proposed in the early 1960s (Mackenzie 1961). Developing the ideas of P. Tedesco (1921: 255) and