Definition
Back matter
Back matter is everything after the main text: acknowledgements, appendices, notes, bibliography, index, about-the-author and any call to action. It is where an indie book earns its next reader.
Conventional order runs appendix, notes, glossary, bibliography, index, then author material. For self-published books the back matter carries commercial weight the front matter cannot: a review request, a link to the next book in the series, and a mailing-list offer all sit here, read by exactly the people who finished. Keep it short and sequenced — the reader who has just closed the story will act on one ask, rarely three.
Related tools & guides
Front matter, chapter openers and scene breaks, set for you
Ceeryo generates the half-title, title and copyright pages, opens chapters on the right-hand page with the running head suppressed, and turns your blank lines and '* * *' into scene breaks — from the manuscript as you wrote it.