Several Dhivehi scripts have been used by Maldivians during their history. The early Dhivehi scripts fell into the abugida category, while the more recent Thaana has characteristics of both an abugida and a true alphabet. An ancient form of Nagari script, as well as the Arabic and Devanagari scripts, have also been extensively used in the Maldives, but with a more restricted function. Latin was official only during a very brief period of the Islands' history. The first Dhivehi script likely appeared in association with the expansion of Buddhism throughout South Asia. This was over two millennia ago, in the Mauryan period, during emperor Ashoka's time. Manuscripts used by Maldivian Buddhist monks were probably written in a script that slowly evolved into a characteristic Dhivehi form. Few of those ancient documents have been discovered and the early forms of the Maldivian script are only found etched on a few coral rocks and copper plates. Ancient scripts (Evēla Akuru) Dhivehi Akuru "island letters" is a script formerly used to write the Dhivehi language. Unlike the modern Thaana script, Divehi Akuru has its origins in the Brahmi script and thus was written from left to right. Dhivehi Akuru was separated into two variants, a more recent and an ancient one and christened "Dives Akuru" and "Evēla Akuru" respectively by Harry Charles Purvis Bell in the early 20th century. Bell was British and studied Maldivian epigraphy when he retired from the colonial government service in Colombo. Bell wrote a monograph on the archaeology, history and epigraphy of the Maldives. He was the first modern scholar to study these ancient writings and he undertook an extensive and serious research on the available epigraphy. The division that Bell made based on the differences he perceived between the two types of Dhivehi scripts is convenient for the study of old Dhivehi documents. Dhives Akuru developed from Brahmi. The oldest attested inscription bears a clear resemblance to South Indian epigraphical records of the sixth-eighth centuries, written in local subtypes of the Brahmi script. The letters on later inscriptions are clearly of the cursive type, strongly reminding of the medieval scripts used in Sri Lanka and South India such as Sinhala, Grantha and Vatteluttu. There are also some elements from the Kannada-Telugu scripts. The early form of this script was also called Divehi Akuru by Maldivians, but it was renamed Evēla Akuru "ancient letters" in a tentative manner