These categories are related as follows:
Sectioning content, heading content, phrasing content, interactive content and embedded content are all types of flow content. A subset of metadata content is also flow content. Embedded content is also phrasing content. Subsets of interactive and metadata content are phrasing content. A subset of the interactive content which is phrasing content is also embedded content.
<object data="http://dev.w3.org/html5/spec/images/content-venn.svg" height="288" width="1000" role="img" aria-label="Venn diagram depicting HTML content category relationships.">
<img src="http://dev.w3.org/html5/spec/images/content-venn.png" alt="Venn diagram depicting HTML content category relationships."></object>
Appears to work as expected in Firefox using NVDA and JAWS. In IE the object and SVG is ignored by JAWS, while NVDA announces the image but not the label. Using VoiceOver and Safari on iPad it works as expected.