"Orality" refers to reliance upon the spoken, rather than written, word for communication. Orality is an ancient phenomenon that continues to the present. Before writing was developed, cultures passed along their cultural traditions, including their history, identity, and religion, through their stories, proverbs, poems, songs, riddles, etc. These are all oral art forms; that is, they are spoken, sung or chanted. They were (and still are) often woven into ceremonies, dramas and rites of passage. Purely oral societies pass along everything that matters from one generation to another without putting anything into writing. They rely on the spoken word (including its sung and chanted forms).
"Purely oral societies pass along everything that matters from one generation to another without putting anything into writing."
That reliance on the spoken word is "orality." But the term means more than that to the experts who study this phenomenon. When people live by orality, it affects a great many things about their culture. If they do not write anything down, for instance, they have to work more on remembering things, so they tend to repeat well-known, treasured sayings and stories. Oral cultures prefer the familiar. It follows that oral cultures may be slow to accept new information, particularly if it does not come in a memorable format.
Oral cultures work at putting every important truth or piece of information into easily-remembered forms. Proverbs are pithy, memorable ways of storing truths. Poems and songs are often easier to remember than simple lists of truths or facts. Oral cultures develop standard ways of structuring proverbs, poems, and stories. Those patterns of organizing spoken language for ease in recall and presentation are also part of "orality."
These are just two facets of orality, but they illustrate that if we want an oral culture to understand a message, it would be helpful to present it in forms that are more familiar to them. By studying orality we get a better understanding of how oral cultures function. That understanding helps us find the best way to present the Bible's message so they can understand it, retain it, benefit from it and pass it to others.