There are two ways to view content on your site: (1) on a landing page (where multiple posts can live in one spot) and (2) in the full-post view (where you're looking at one individual post, fully displayed).
Landing page view - multiple teasers
Typically, when you click on a navigation term you wind up on a landing page. Landing pages are designed to display multiple posts, often in "teaser" format where only part of the post shows, and there is a read more at the end that takes you to the full-post view. (Note: it is possible to redirect a navigation term to a post, but that's a story for another day...)
In this example, multiple posts have been tagged to the Meet the Team navigation term, and only the content up to the teaser break for each post displays. (Note that you *could* put the teaser break at the end of any of the posts if you wanted the whole post to show on the landing page.)
On landing pages, you will typically see the section navigation on the left, with the parent term at the top and siblings, as well as the current term you're on, below it.
The full post view
If you click the first post (in this case, Mac Clemmens), you'll see that the display is different and the entire content shows, including a bit more body text that was below the teaser break.
Full posts will show different types of content based upon their post type and the fields that have been completed. In this case you see contact information for Mac on the right, and blog posts he has written below. (In this instance the blog posts are actually related content for his profile.)
Full posts will also display the "back" link on the left, above any terms the post is tagged to - in this case, Meet the Team.