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, 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.