Hi again
So a preface in a non-fiction/academic book will explain how the author came to be acquainted with the chosen subject matter. This should discuss methodology, sources and the central theme of the book. The preface also establishes the credentials of the author. It should also establish the research made into the subject matter. It should be a formal text to ease and to introduce the reader to the subject matter.
A preface in a fiction book is a prologue. I think.
Sorry to labour this point but it's good to know these things.
Jen
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