by Christian communities: a cursive form known as the Syriac alphabet. A highly modified form of the Aramaic alphabet, the Mandaic alphabet, is used by the Mandaeans. In addition to these writing systems, certain derivatives of the Aramaic alphabet were used in ancient times by particular groups: the Nabataean alphabet in Petra and the Palmyrene alphabet in Palmyra. In modern times, Turoyo (see below) has sometimes been written in a Latin script. Periodization Periodization of historical development of Aramaic language has been the subject of particular interest for scholars, who proposed several types of periodization, based on linguistic, chronological and territorial criteria. Overlapping terminology, used in different periodizations, led to the creation of several polysemic terms, that are used differently among scholars. Terms like: Old Aramaic, Ancient Aramaic, Early Aramaic, Middle Aramaic, Late Aramaic (and some others, like Paleo-Aramaic), were used in various meanings, thus referring (in scope or substance) to different stages in historical development of Aramaic language. Most commonly used types of periodization are those of Klaus Beyer and Joseph Fitzmyer. Periodization of Klaus Beyer (1929–2014): Old Aramaic, from the earliest records, to 200 AD Middle Aramaic, from 200 AD, to 1200 AD Modern Aramaic, from 1200 AD, up to the modern times Periodization of Joseph Fitzmyer (1920–2016): Old Aramaic, from the earliest records, to regional prominence 700 BC Official Aramaic, from 700 BC, to 200 BC Middle Aramaic, from 200 BC, to 200 AD Late Aramaic, from 200 AD, to 700 AD Modern Aramaic, from 700 AD, up to the modern times Recent periodization of Aaron Butts: Old Aramaic, from the earliest records, to 538 BC Achaemenid Aramaic, from 538 BC, to 333 BC Middle Aramaic, from 333 BC, to 200 AD Late Aramaic, from 200 AD, to 1200 AD Neo-Aramaic, from 1200 AD, up to the modern times Old Aramaic Aramaic's long history and diverse and widespread use has led to the development of many divergent varieties, which are sometimes considered dialects, though they have become distinct enough over time that they are now sometimes considered separate languages. Therefore, there is not one singular, static Aramaic language; each time and place rather has had its own variation. The more widely spoken Eastern Aramaic and Mandaic forms are largely restricted to Assyrian Christian and Mandean gnostic communities in Iraq, northeastern Syria, northwestern Iran and southeastern Turkey, whilst the severely endangered Western Neo-Aramaic is spoken by small communities