Yes, the blue indicates that the text is linked to a hub. What you do is take your cursor and swipe it across the words that you want to link to another hub or another article (it can even be someone else's from another website). Then click on the hyperlink icon on the toolbar at the top of the capsule that your text is located in. It will suggest some of your own hubs that you may want to choose from or you can add the url of something else. You'll see the URL space at the top. Now, before you save you should set it to open in a new window. Not everyone does this but you'll keep your readers from getting lost off your page when they click the link. I have a hub called Readers-How to Keep Them that will tell you how to do this.