oral tradition

n. orally transmitted traditions and laws

Oral tradition or oral culture is a way for a society to transmit history, literature, law or other knowledge across generations without a writing system. An example that combined aspects of oral literature and oral history, before eventually being set down in writing, is the Homeric epic poetry of the Iliad and the Odyssey. In a general sense, "oral tradition" refers to the transmission of cultural material through vocal utterance, and was long held to be a key descriptor of folklore (a criterion no longer rigidly held by all folklorists). As an academic discipline, it refers both to a method and the objects studied by the method.
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n. ประวัติและขนมธรรมเนียมถ่ายทอดสู่รุ่นต่อไปโดยเล่าปากเปล่า