As you may be able to tell, the study of communication was based in the oral tradition. The oral tradition refers to the vocal transmission of information between people from generation to generation.
History, law, tradition, culture—all were passed along by orally for centuries prior to the creation of the written word. Even after the written word was invented, the 'oral tradition' remained intact due to the prevalence of illiteracy. Even today there are still traces of the power of the “oral tradition.”
For example, some nursery rhymes, such as Humpty Dumpty, date back to 16th century England. Did you ever sing it as a child? Well, you many not know it refers to a cannon used in the English Civil War which fell from its perch atop a church wall when, in 1648, it was hit by enemy fire.
It can be hard to believe, given that we live in a mass and computermediated society, that at one time the spoken word was the primary medium of communication, even over the written word."
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Public Speaking Project (2011) Public Speaking: The Virtual Textbook. Retrieved from http://www.publicspeakingproject.org/psvirtualtext.html