History of the Greek alphabet retained the sound. A symbol based on the left-hand half ( ├ ) of the letter Η was therefore sometimes used to indicate the presence of where necessary, and its absence was indicated by a symbol based on the right half. During the classical period, ΕΙ came to be pronounced and ΟΥ came to be pronounced , Υ having meanwhile moved to . By about 200 BC, a system of diacritical marks was invented, representing the tone accents in use in Ancient Greek. This also helped to indicate the length of the vowels Α, Ι, and Υ in certain cases
Greek alphabet by the foundation of the Phi Beta Kappa Society at the College of William and Mary in 1776. The name of this fraternal organization is an acronym for the ancient Greek phrase Φιλοσοφία Βίου Κυβερνήτης ("Philosophia Biou Kybernētēs"), which means "Love of wisdom, the guide of life" and serves as the organization's motto. Sometimes early fraternal organizations were known by their Greek letter names because the mottos that these names stood for were secret and revealed only to members of the fraternity. The Greek letter names of most fraternal organizations today are meaningless and do not stand for anything, which