IDU

IDU can refer to:International Democrat UnionInternational Dance UnionInjecting Drug UserInterface Data Unit
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Idu is an archaic writing system which represents the Korean language using hanja. The term "idu" is used in two senses. It may refer to various systems of representing Korean phonology through Chinese characters, which were used from Silla to Joseon periods. In this sense it includes hyangchal and gugyeol writing, as well as the narrower sense of "idu." The narrower sense refers solely to the system developed in the Goryeo period, and first referred to by name in the Jewang Ungi.
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