Ancient Greek phonology is the reconstructed phonology or pronunciation of Ancient Greek. This article mostly deals with the pronunciation of the standard Attic dialect of the fifth century BC, used by Plato and other Classical Greek writers, and touches on other dialects spoken at the same time or earlier. The pronunciation of Ancient Greek is not known from direct observation, but determined from other types of evidence. Some details regarding the pronunciation of Attic Greek and other Ancient Greek dialects are unknown, but it is generally agreed that Attic Greek had certain features not present in English or Modern Greek, such as a three-way distinction between voiced, voiceless, and aspirated stops (such as , as in English "bot, spot, pot"); a distinction between single and double consonants and short and long vowels in most positions in a word; and a word accent that involved pitch. Koine Greek, the variety of Greek used after the conquests of Alexander the Great in the fourth century BC, is sometimes included in Ancient Greek, but its pronunciation is described in Koine Greek phonology. For disagreements with the reconstruction given here, see below. Dialects Ancient Greek was a pluricentric language, consisting of many dialects. All Greek dialects derive from Proto-Greek and they share certain characteristics, but there were also distinct differences in pronunciation. For instance, the form of Doric in Crete had a digraph , which likely stood for a sound not present in Attic. The early form of Ionic in which the Iliad and Odyssey were composed (Homeric), and the Aeolic dialect of Sappho, likely had the phoneme at the beginnings of words, sometimes represented by the letter digamma , but it had been lost in the standard Attic dialect. The pluricentric nature of Ancient Greek differs from that of Latin, which was composed of basically one variety from the earliest Old Latin texts until Classical Latin. Latin only formed dialects once it was spread over Europe by the Roman Empire; these Vulgar Latin dialects became the Romance languages. The main dialect groups of Ancient Greek are Arcadocypriot, Aeolic, Doric, Ionic, and Attic. These form two main groups: East Greek, which includes Arcadocypriot, Aeolic, Ionic, and Attic, and West Greek, which consists of Doric along with Northwest Greek and Achaean. Of the main dialects, all but Arcadocypriot have literature in them. The Ancient Greek literary dialects do not necessarily represent the native speech of