is descended from the Semitic letter vau, which the Greeks borrowed for their vowel upsilon (or ypsilon) and the consonsant digamma. The Romans added it late in the development of their alphabet, replacing their U (written as V) for it as Greek words were added to the language. Most scholars date Ys creation to 1st century AD when Z was also added. Y has long been considered a philosophical letter — a symbol of moral decision — because of its forked top. It is also known as the Pythagorean letter because Pythagous is suspected of inventing it.Y continues to be used as both consonant & vowel (the "fifth vowel") in modern English. Its sound is closely related to I, and both Latin and Old English used the two letters interchangeably. Y was also used as a substitute for the Old English thorn and is still used in phrases like “ye olde tavern”. Y is phoenetically known as a voiced palatial spirant.
