<p>Atlas supports four different markup languages: HTML, markdown, asciidoc, and docbook. To use the Visual Editor, write your project in HTML making sure to adhere to the HTMLBook spec, or just use the Visual Editor right from the beginning (it already follows the HTMLBook rules).</p>
<p>What is a section?</p>
<p>An integral part of the HTMLBook spec is the concept of sections. </p>
<p>Hover over this paragraph of text. See that blue line that appears? That line helps you insert a new block after this paragraph. By default, the line will insert just a plain paragraph, but once you do that, you can use the Insert... menu to change it into a whole new section, or a sidebar, note, or some other book element.</p>