There is a lot of stupid and confusing info for formatting your book for Amazon Kindle. These are the best guides I’ve found so far.
https://kdp.amazon.com/help?topicId=A17W8UM0MMSQX6
http://johnaugust.com/2009/kindle-formatting-for-web-geeks
The ebook Design and Development Guide by Paul Salvette
http://derekjcanyon.blogspot.com/2010/10/step-by-by-step-kindle-ebook-html.html
http://kindleformatting.com/formatting.php
From Kindle Formatting:
Use the custom
<mbp:pagebreak />tags to mark pagebreaks in the text. I suggest you include one in front of every chapter or section.The Kindle has built-in bookmarks for the Table of Contents and the start of the book’s content. Use the following anchor tags to mark those places in your book:
<a name="TOC"/>and<a name="start"/>. Place the anchors right after the page break tag, before any headings or paragraphs.