For best results, WikiAuthors should avoid putting Level 1 (<h1>) Headings in wiki pages. Instead use Levels 2 (!! markup) through 6 (!!!!!! markup) without skipping levels. L2 to L6 without skipping levels improves a page's structure and increases accessibility and discoverability of the page's content because headings establish a page outline. This editorial note is normal paragraph text. --Hagan
Indented text - A page's outline is meaningful when the page is parsed by machines (e.g. screen readers and search-engine spiders). See this page's outline here. Conventionally <h1> headings are used only once per page as the page's main heading. Some skins—including the default PmWiki Skin—tag the page's title with an <h1> tag to improve content accessibility and discoverability.
Hanging text - The W3C explains it this way: "When looking at the content, the highest available heading level should be used to mark up the heading of the main content, as this makes it easy to discover. Ideally use an <h1> or <h2>." You can also improve accessibility and discoverability by adding page (:description:) text, adding alt-text to images, and adding link titles to links in your pages.
Normal paragraph text next to a right-floated image using %rfloat%WikiStyle markup - PmWiki doesn't make any attempt to do everything that can be done in HTML. There are good reasons that people don't use web browsers to edit HTML--it's just not very effective. If you need to be writing lots of funky HTML in a web page, then PmWiki is not what you should be using to create it. What PmWiki does try to do is make it easy to link PmWiki to other "non-wiki" web documents, to embed PmWiki pages inside of complex web pages, and to allow other web documents to easily link to PmWiki.