A preface is an introductory section of a book that comes before the main text and is written by the author. It explains how and why the book came into being, and what challenges the author faced in the process. The preface is where the author can provide context for the book and give readers a glimpse into what they can expect from the content. It is also an opportunity for the author to sell readers on their book and draw them in. Unlike a foreword, which is written by someone other than the author and lends credibility to the book, the preface is written by the author. The introduction, on the other hand, is the first part of the main text and provides a brief primer on the topic that readers may not be familiar with yet.