The preface is often confused with the foreword and introduction. Unlike the foreword, the preface should always be written by the author. The preface is separate from the content, and it allows the author to explain why he or she wrote the book and potentially how to use it. For example, a memoirist might use an anecdote to explain how writing her story was therapeutic, and that the book could be helpful for studying dysfunctional family dynamics.
Preface, Introduction or Foreword
Prefaces, introductions and forewords are all potential opening sections of a book, and each has a specific, proper usage. While a preface explains the author's personal connection with the material, an introduction often summarizes the content. A foreword, conversely, is an opening written by someone else, such as an expert or established author, who endorses the book and details why it is worthy of being read. Of these three potential opening modes, a preface is most closely related to narrative nonfiction, such as biographies, autobiographies and memoirs, as well as instructional books. This relationship exists with narratives because the author is attempting to forge a trusting connection with the reader and wants to establish his or her agenda with the book. In this way, a preface can share characteristics of a prologue in that it can also contain brief stories or anecdotes. The difference, however, is that a preface will always contain at least one section in which the author speaks directly to the reader about the project and purpose of the book.