Emphasis allows for paragraph level linking and highlighting. Seward explains its magic:
To get started, hit shift twice. I love that. Ryan Sholin noted today that he had also installed Emphasis, and it occurred to me that as the tool spreads, double-tapping shift becomes a sort of shibboleth: Are you enabled for deep links? And if the answer is yes, pilcrows appear.
At that point, you can link to any paragraph by clicking on its pilcrow. Highlight by clicking on a paragraph and then any sentences within it that you wish to emphasize. Your new URL awaits in the address bar.
As Seward points out, paragraph-level linking adds value for users and authors. If one of the goals of the web is to save the user time, Emphasis is a nice tool that allows publishers to do just that.
Try it out for yourself: just tap Shift twice.