History of the Greek alphabet only required one. The history here is complicated, but basically "sāmekh" dropped out in certain dialects, and was reused to represent in others, while usage for the sound varied between "ṣādē" and "šin". The letter now known as sigma took its name from "sāmekh" but its form from "šin", while the letter San, which occurred in a few dialects only, took its name from "šin" but its place in the alphabet from "ṣādē". A further Greek letter of uncertain origin, sampi, is found occasionally, and may represent an affricate, such as . For the special case of zeta, see Zeta
Greek alphabet of these letters is a matter of some debate. Three of the original Phoenician letters dropped out of use before the alphabet took its classical shape: the letter Ϻ ("san"), which had been in competition with Σ ("sigma") denoting the same phoneme /s/; the letter Ϙ ("qoppa"), which was redundant with Κ ("kappa") for /k/, and Ϝ ("digamma"), whose sound value /w/ dropped out of the spoken language before or during the classical period. Greek was originally written predominantly from right to left, just like Phoenician, but scribes could freely alternate between directions. For a time, a writing style with