Someone other than the author of the book usually writes the foreword. That person is typically an authority in the field who can establish integrity of the author. The interaction between the writer of the foreword and the author of the book is usually addressed. The foreword is often signed with the author's name, place and date.
The foreword is placed after the table of contents. The pages are numbered with lower-case Roman numerals rather than the Arabic numerals used for the rest of the book. As a marketing tool, the foreword may be used to market both the foreword writer and the author of the book. The forward writer explains the purposes and the goals of the work, and may also place the work in a context, as well as spell out the organization and scope of the book.
The introduction is a mini essay written by the author or an editor that describes the topic of a book. The introduction can be considered as a preview of what is to come in the rest of the book. The Introduction explains the author's point of view and may suggest how the reader will benefit from reading the book. A good introduction sets the stage for the reader and makes the book more appealing.
The introduction is placed after the foreword. The pages of the Introduction are usually numbered using the same numbering system as the rest of the book.
Introductions are also sometimes used as marketing tools and may be be excerpted on the book jacket or in other places to enable readers to know the benefits of reading the book.