The Kurdish languages (Kurdî, کوردی; IPA: [ˈkuɾdiː]) constitute a dialect continuum spoken by Kurds in Kurdistan and the diaspora. The three Kurdish languages are Kurmanji (Northern Kurdish), Sorani (Central Kurdish), and Southern Kurdish (Palewani or Xwarig/Xwarîn). A separate group of non-Kurdish Northwestern Iranian languages, the Zaza–Gorani languages, are also spoken by several million ethnic Kurds. Studies as of 2009 estimate between 8 and 20 million native Kurdish speakers in Turkey. The majority of the Kurds speak Kurmanji ("Northern Kurdish"). The classification of Laki as a sub-dialect of Southern Kurdish or as a fourth dialect of Kurdish is unsettled, 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 began to be developed. Today, there are two principal written Kurdish dialects, namely Northern Kurdish in the northern parts of the geographical region of Kurdistan and Central Kurdish further east and south. Central Kurdish is, along with Arabic, one of the two official languages of Iraq and is in political documents simply referred to as "Kurdish".
(Courtesy of Kurdish Language Wikipedia)