Prologue, Foreword, Introduction, or Preface?
Surprisingly, these four things are NOT synonyms.
1. Foreword - written by someone other than you, the author. Usually someone of the same field - it's like a recommendation from someone who follows the same path
Note: Often misspelled, "forward." I'm not even kidding! Go check your draft.
2. Preface - if you want to talk more about the journey of how this book came to be, this is the place. Or, if you want to do more than just mention a name in acknowledgment of how grateful you are for the help you've had in the creation of your book, you can expound upon it here.
3. Prologue - For fiction. You can think of it as a snippet of the book to garnish interest. It's told from the POV of the main character. In the same manner, one might write an epilogue as a sort of after the fact wrap up of events.
4. Introduction - For non-fiction. "Tell me about what you're going to tell me about," as my 4th grade teacher used to say.
What else might come in the front portion of a book? The title page obviously, as well as the copyright information page, perhaps an acknowledgments page to your parents, spouse, children, editor, designer, and even beta reader friends. There's usually a blank first page requirement, for those of you self publishing. Note: It's copyright, not copywrite. You're welcome. 2 freebies in one post? Hire me now!
Check out these great articles for suggestions about the order these come in, and more: