Proem redirects here. For the musician, see Proem . For preface in liturgy, see Preface . A preface is an introduction to a book written by the author of the book. An introductory essay written by a different person is a foreword and precedes an author's preface. The preface often closes with acknowledgements of those who assisted in the project. A preface generally covers the story of how the book came into being, or how the idea for the book was developed; this is often followed by thanks and acknowledgments to people who were helpful to the author during the time of writing. A preface is usually signed (and the date and place of writing often follow the typeset signature); a foreword by another person is always signed. Information essential to the main text is generally placed in a set of explanatory notes, or perhaps in an "Introduction" that may be paginated with Arabic numer