So in here I type in all of the copy. The idea being that this is the full article, not just a snippet.
To this I can add as much or as little copy as I like, plus upload pictures or include links to other things such as other websites, newsletters, whatever you want.
The snippet (or first paragraph or first sentence or two) would go into your newsletter. At the bottom of that snippet, you might have a READ MORE link or similar. That READ MORE link directs the reader to this page.