The doc page is where you read a result.
Layout
The document in the middle, navigation on the left, and its structure on the right. Long documents get a contents list you can jump around with.
The sidebar
Groups expand and collapse, and remember their state.
Favorites
Pin a doc, project or issue and it stays in the sidebar.
Versions
Every doc keeps its history. The version selector in the header opens earlier versions. See Docs and versions.
Switching directories
The directory menu swaps which organisation you are looking at while keeping you on the same kind of page.